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In order to fully understand the current research situation in field of deep coal mining, took the relevant literature of web of science database from 2003 to 2021 as a sample, this paper made an in-depth analysis on the number of papers issued, research institutions, countries, authors, literature citations, keywords and disciplines.The results showed that China's research level is at the forefront of the world in terms of the number of papers issued, research institutions and national levels; Chinese scholars pay high attention to this field in terms of the author; highly cited documents are mostly engineering and technical studies in terms of literature citation; from the perspective of keyword development and evolution, the keywords in this field mainly focus on model, rock, numerical simulation, mechanism and stress, model and numerical simulation will be the important research methods in this field in the future.From the perspective of discipline development and evolution, disciplines in this field mainly focus on engineering, geology, multidisciplinary geoscience, energy and fuel, environmental science and ecology, sustainable development will become the hot research directions in the future.

The highly-efficient treatment of coal mine water with low energy consumption contributes to much safer and more efficient coal mining. At present, mine water processing at underground is still limited for its small treatment water yield, large land coverage and high operation cost in ground treatment, high drainage costs when mine water is discharged into the surface water system. In this light, this study puts forward the "deep ground-underground-surface ground" linkage system for mine water treatment and utilization. The treated mine water is partially used for mining production and residential usage, while the rest is subject to deep reinjection or drainage. This paper first introduces the operational mechanism behind this system, and then evaluates its validity in terms of water quality, water quantity, hydrogeology, underground structure, and feasibility of recharge engineering. This study then reviews existing mine water treatment methods for varying water qualities and the "underground-surface" joint treatment system; Also, a summary is drawn regarding the selection of aquifer for reinjection purposes, reinjection construction operations, reinjection tests, simulation of reinjection water quality, and analysis of reinjection safety.

The optical fiber inertial navigation of coal mine excavation equipment is easy to be disturbed by multi-source heterogeneous noise such as vibration and electromagnetism in the underground excavation face, which leads to the reduction of the accuracy of position and attitude detection of excavation equipment. Therefore, in order to eliminate the influence of noise interference on the positioning and detection of integrated inertial navigation, a multi-source heterogeneous noise reduction method of optical fiber inertial navigation based on improved empirical mode decomposition (EMD) is proposed. Firstly, according to the environmental noise characteristics of underground heading face, the composition and characteristics of multi-source heterogeneous noise are analyzed. Then, the improved EMD noise reduction method is used to reduce the multi-source heterogeneous noise of optical fiber inertial navigation. This method adaptively selects the effective eigenmode function (IMF) by calculating the continuous mean square error (CMSE), optimizes the effective IMF component of each layer by setting the threshold function, and reconstructs the optimized effective IMF component, so as to obtain the signal after noise reduction. In order to verify the noise reduction effect of the improved EMD method, the comparative experiments of wavelet noise reduction method, variational modal decomposition (VMD) noise reduction method and improved EMD noise reduction method are carried out. The results show that the noise reduction effect of the improved EMD noise reduction method is better than that of wavelet noise reduction and VMD noise reduction method. In order to verify the improvement effect of the improved EMD Method on the pose detection accuracy of tunneling equipment, the combined positioning results of optical fiber inertial navigation and displacement sensor before noise reduction and after noise reduction by three noise reduction methods are compared and analyzed. The results show that the pose error of the combined positioning after noise reduction of optical fiber inertial navigation signal by the improved EMD method is the smallest, and it is greatly reduced compared with that before noise reduction, The Pitch angle error decreased from 0.1131° to 0.0286°, the Roll angle error decreased from 0.0101° to 0.0038°, the Yaw angle error decreased from 2.7051° to 0.0272°, the North position error decreased from 36.8872 to 0.0822 m, the East position error decreased from 0.4990 to 0.0161 m, and the Upward position error decreased from 0.9141 to 0.0143 m. The improved EMD noise reduction method proposed in this paper can effectively filter the multi-source heterogeneous noise of optical fiber strapdown inertial navigation signal of coal mine excavation equipment, which lays a good foundation for the accurate positioning of coal mine excavation equipment.

The resource utilization of coal mine drainage has been attracting growing attention. The increasingly stringent discharge standards and the deepening of the concept of intelligent mine have posed new challenges to mine water treatment technology. This paper discussed the traditional treatment processes and the multi-stage filtration underground treatment technology. In addition, a new high-efficiency technology-Polycera membrane ultrafiltration-was proposed to treat coal mine drainage on the basis of summarizing the existing technology problems. Compared with the multi-process of the traditional treatment technology, the new technology only includes two main units, high pressure pretreatment and atmospheric filtration treatment, because the treatment process does not need dosing and the whole dosing system can be omitted, which solves the problem that the traditional coal mine drainage treatment method must add coagulant, and can truly make the whole process of coal mine drainage treatment unattended and meet the requirements of the intelligent mine. The new technology offers the advantage of a shorter process flow and a smaller footprint and could ensure the stability of effluent water quality. Besides, the new technology could be operated automatically without chemical additions. At the same time, it can realize modularization and intellectualization, and can be applied to the direct filtration of coal mine drainage containing high suspended solids in different scenarios, or as the pretreatment unit of coal mine drainage brackish water, especially suitable for the in-situ reuse of coal mine drainage underground treatment. The core component of the new technology is the Polycera membrane with high strength and high-water flux. It is a super hydrophilic and oleophobic material that can withstand suspended solids (SS) of high concentrations up to 10000 mg/L. By analyzing the laboratory-scale test results and the reconstruction engineering case of coal mine drainage treatment on the ground, it can be seen that in the range of inlet SS of 0-10000 mg/L, the SS of the filtered effluent after direct filtration with Polycera membrane can be stably below 1 mg/L, and the turbidity can be stably below 1NTU, it is shown that the new technology presents apparent advantages in the resource utilization of coal mine drainage. This technology could provide a technical reference for large-scale engineering applications in the future.

Concealed hazard sources in the working face are the main hidden danger for safe production in the coal mines, and the Radar Travel Time Tomography technology can realize the high-precision detection of the concealed hazard source in the large-span working face.This paper puts forward an evaluation criteria for tomographic accuracy, including the evaluation indicators of variance of velocity difference between inversion velocity field and actual velocity field, deviation degree of the inversion center of the anomalous body, and deviation degree of the size of the anomalous body.Then the influence of radar traveling time tomography by point spacing, transmitting angle and inversion grid in mine is analyzed through forward modeling, resulting in the optimized parameters for observation system and inversion.Finally, the optimized parameters are employed to carry out some field verification experiments, and the results show that the anomalous body can be detected affectively for the working face within 100 m span, providing effective technical support for the rapid and precise detection of concealed hazard sources in large-span working face in mine area.

The paper analyzed general structure of existing power supply monitoring and control systems of coal mine and difference in structure of the systems.It described functions of power supply monitoring and control system of coal mine in details,and discussed development trend of power supply monitoring and control system of coal mine from the view of system structure,software and hardware and system's function.The paper has some value to the development of power supply monitoring and control technology of coal mine.

Based on database of collected gas monitoring information of coal mine monitoring system in coal mine production process,the paper put forward a scheme of using clustering analysis method based on DBSCAN algorithm to mining characteristics of gas accident information.It pointed out shortage of DBSCAN algorithm in practical application,proposed an improved scheme of DBSCAN algorithm based on data partition,and introduced the concrete improving method.The result of applying the clustering analysis method based on the improved DBSCAN algorithm to make clustering analysis and extract of information feature of gas monitoring data of coal mine showed that the method is effective.At last,the paper pointed out the farther research direction of the method.

According to characteristics of complex structure and various interconnection equipments with increasing quantity of coal mine monitoring and control system,the paper analyzed applicability of traditional authentication method of intrinsically safe interconnection system in China,interface parameter authentication method in the other countries and a series of intrinsically safe standards to intrinsically safe interconnection authentication of coal mine monitoring and control system in China,pointed out that the judging criterion of intrinsically safe performance of coal mine monitoring and control system is GB3836.4-2000 equ IEC 60079-11:1999 at present,and proposed a scheme that intrinsically safe interconnection authentication of non-bus mode interface equipments of coal mine monitoring and control system uses parameter authentication method and the authentication of bus mode interface equipments should use system authentication method at present.It introduced implementing key points...更多 of parameter authentication method and system authentication method in details and the way of implementing parameter authentication of intrinsically safe interconnection of bus mode interface equipments in the future.In addition,it proposed design principle of interface equipments of coal mine monitoring and control system and further research direction of authentication method of intrinsically safe interconnection of coal mine monitoring and control system.The paper will be good for development of parameter authentication method of intrinsically safe interconnection of interface equipments of coal mine monitoring and control system.

To solve the problem of the error of frequency measurement algorithm with time-varying frequency in mine power supply system, an improved software zero-crossing algorithm is proposed.The relationship among the phase angle, the time and the frequency of the voltage of the system is established.The relation formula between the real-time frequency and the period of zero-crossing point is derived when rate of frequency variation is not zero according to the relationship between two adjacent with the direction of the zero-crossing phase difference of 2π.The exact calculation formula of the period is obtained by using the Newton three interpolation polynomial, the Newton iteration method and the Qin Jiushao algorithm.Hence, the frequency and rate of frequency variation can be obtained.A variety of situations , including signals without harmonics, signals with harmonics and random noise, as well as the frequency rapid decline process in system failure, are simulated using MATLAB, The simulation results show that the algorithm of this paper can accurately measure the real-time frequency of the system and rate of frequency variation in above situations, and this method is superior to conventional zero-crossing algorithm in measurement accuracy, instantaneity and computation.This algorithm is suitable for application of protection, control and monitoring devices and automation equipment in mine intelligent power supply system.

The paper pointed out that building ontology model of heading face was an important step towards the construction of intelligent decision-making system based on deep analysis of production model of the heading face, obtained relationship between the staff, devices and environment of underground heading face by analyzing factors of mine production safety, and built safety production ontology model of the heading face. Hazardous workplace was taken as an example to simply verify the validity of construction method of the ontology model of heading face.

The paper analyzed accident rate per million tons, death rate per million tons, serious accident rate per one hundred million tons and serious accident death rate per one hundred million tons during 2004-2013. It proposed intelligent unmanned steer methods of rubber-tyred vehicle and electric locomotive, and navigation control method of mine-used robots and disaster rescue robots which mixed with machine vision, laser ranging, radar ranging and velocity measurement and artificial intelligence. It studied characteristics of mine-used machine vision and its application in coal mine. It put forward that underground mobile communication mainly uses 4G and WiFi technologies, and 5G mobile communication with faster transmission speed and higher working frequency which is more suitable for underground. It pointed out that radio wave with larger radiation power not only ignites gas and electric detonator, but also causes personal injury. It also pointed out antenna with larger transmission power and gain should be installed on top of roadway and far away from fixed post operating personnel, so as to avoid radiation for long time. It proposed mine-used robots and disaster rescue robots should employ unmanned rotorcraft with lithium battery and high power micro motor, and technologies of remote wireless control and automatic navigation control of underground robots should be studied. It put forward monitoring and early warning methods for fire disaster in goaf based on gas and temperature remote measuring sensors. It put forward technology requirements of monitoring for preventing coal mining illegally. It analyzed advantages and shortcomings of underground visible light communication.

In view of problem that existing image fuzzy enhancement algorithm of underground coal mine cannot deal with the situation when the image is in fog and the processed images are obscure, the paper proposed an enhancement technique of underground image based on dark channel prior. The technique uses linear fuzzification function to achieve the purpose of image enhancement, and adopts dark channel prior theory to enhance image contrast, meanwhile realizes defogging and dedusting. The experimental results show that the proposed technique can improve visibility of underground image and significantly enhance image contrast.

The paper analyzed the national coal production，the total number of accidents, the death rate per million tons and the changes of serious accidents. On average per year, the coal production had increased by 194 million tons, the number of accidents had decreased by 337, the death number of personnel had decreased by 551 and the death rate per million tons had decreased by 0.310.It proposed that mine-used thermal catalytic methane sensor should be used in low gas mine and high gas mine, mine-used laser methane sensor should be used in coal (rock) and gas outburst mine; mine-used wireless sensor should be used in the upper corner of working face, on heading face, in high risk location and on mining equipment and transportation equipment, and the mine-used wireless sensor should use wireless power transmission to supply power; mine-used gas telemetering sensor should be used for gas detection in inconvenient place for people to reach such as area of harmful gas advanced detection by the rescue team, the area of goaf and high risk roof; the automatic zero set of sensor should be used in portable gas detector and wireless sensor. It also put forward axial layout method and serpentine layout method for monitoring fire accident in goaf of mine-used distributed fiber temperature measurement system; the mine-used distributed fiber temperature measurement system should be used to monitor fire accident of underground coal mine belt, cable and electrical equipment. Meanwhile, it proposed that automatic coal mining should use memory coal cut mode based on coal mining model and remote control method, energy saving control of belt conveyor should use laser belt scale and mine power supply system should use fiber longitudinal differential protection and fiber interlock and comprehensive anti override trip system.

In view of problem that stray currents generate serious threat to safety production of coal mine, the paper proposed detection system of stray currents in coal mine based on magnetoresistance effects. It introduced detection principle of the system, designed detection circuit and sensor peripheral circuit, and completed experiment. The experimental result shows that the system can measure stray current accurately and stably, current detection accuracy basically meets detection requirements and the non-contact method is safe and reliable. The proposed system has great practical significance for mine stray current control.

The paper introduced scheme selection, system composition and function characteristics of mine-used TD-SCDMA wireless communication system in details, and expounded application of mine-used TD-SCDMA wireless communication system in Lushuidong Coal Mine. The application results show that the system has stable and reliable performance, large capacity, good effect of calls, large base station coverage, and can meet needs of mobile communication in coal mine underground.

The paper put forward the revision of Coal Mine Safety Regulation should add content of mine mobile communication, broadcast communication, video surveillance, personnel positioning, coal production monitoring, monitoring of mine fire, mine pressure, hydrological monitoring and remote monitoring and so on. It presented that mine monitoring system sharing channel with video surveillance system is forbidden, the cable of dispatching communication system should be dedicated devices of the system, the trunk network should adopt mine Ethernet optical network with volume of gigabit or gigabit above which has function of redundancy, and mine mobile devices and wireless access should be preferred WiFi, ZigBee, 4G technologies. It put forward the core optical fiber and cable for coal mine safety monitoring system and dispatching communication system should be set up separately from different wellbores or different locations of a shaft into the underground, the optical fiber and cable should be provided with protection measures, and the optical fiber and cable should be buried under roadway floor crossover with laneway's side at the pit without serious floor heave. It put forward coal mine safety monitoring system should be equipped with functions of main ventilator monitoring, gas extraction monitoring, real-time on-line monitoring both for the breathing dust density and total dust concentration, air direction monitoring, and analysis of gas change rate, alarm of coal and gas outburst. It also presented that methane sensor for highly gassy and coal (rock) and gas outburst mines should be full range of high-low concentration which preference is given to laser or infrared methane sensor; methane detection equipment such as carrier catalytic element of methane sensor and portable methane detection alarming device should be calibrated regularly with standard gas and air sample, and the calibration is needed at least once every 15 days; methane overrun power cut function test is needed at least once every 15 days; mining face at the highly gassy and coal (rock) and gas outburst mines should setup methane sensor in upper corner which gas concentration for overrun alarm limit is 1.0% CH4, gas concentration for power cut limit is 1.5% CH4, and gas concentration for power regain limit is 1.0% CH4.

The paper analyzed problems existed in traditional coal mine safety monitoring and control system and proposed an architecture of coal mine safety monitoring and control system based on Internet of Things. It introduced key technologies used by sensing layer, transmission layer, persistence layer and application layer in the architecture. The architecture has reference for development of coal mine safety monitoring and control system.

Taking AC three-phase asynchronous motor as research object, the paper analyzed vector control theory of asynchronous motor, and established simulation model of vector control system of asynchronous motor for trackless rubber-tyred electric vehicle and did simulation. The simulation results show that the vector control system has good steady and dynamic performance.

For problems such as unable to determine position of mine locomotive of existing scheduling system of mine railway transportation precisely, the paper proposed a design scheme of intelligent scheduling system of mine railway transportation. The system uses wireless relay platform to achieve locomotive-ground two-way information exchange, uses RFID technology to achieve precise positioning of locomotive, and can dynamically calculates safe distance of the running locomotives according to their speed and position, so as to realize moving block and improve traffic density.

The paper analyzed heat disaster status of local region in deep mining of Xuzhuang Coal Mine and design requirements of underground local refrigeration cooling system. It proposed local mobile and mechanical refrigeration cooling method which is suitable for Xuzhuang Coal Mine：use closed-loop water system, and use two TS-300B underground refrigeration devices for refrigeration cooling of -750 west track roadway and belt transportation roadway respectively. It introduced design scheme, testing result of cooling effect and benefit analysis of refrigeration cooling system. Field application result shows that the system has greatly improved underground work environment, attendance and productivity of workers in high-temperature conditions, but there are still issues that heat exhaust of the refrigeration device is easily affected by environment, spray water of condenser has great loss and so on.

In view of problem that life of lithium battery in miner lamp with lithium battery is closely related to charging and discharging method, the paper proposed a design scheme of an intelligent charging cabinet for miner lamp with lithium battery. It introduced hardware design of unit of charging and management of miner lamp and middle computer of the charging cabinet. Actual application shows that the charging cabinet can accurately control charging voltage and current of lithium battery of miner lamp, and can collect information of whether on shelf and charging state of miner lamp, which improves information level of management of miner lamp.

The paper briefly reviewed development history of through-the-earth communication system, introduced research status and application effect of through-the-earth communication system of domestic and foreign, analyzed current mainstream technology of the through-the-earth communication, and prospected application and development direction of the through-the-earth communication technology in coal mine.

For problems that reliable information is easily destroyed and query efficiency is low existed in underground personnel positioning and management system, the paper designed a data acquisition model and data flow diagrams of the system, and analyzed design requirements, table structure design and database optimization. The system uses master-slave communication mode to achieve data acquisition, establishes foundation database and current database according to different functions, and adopts query sentence optimization and index optimization to improve database performance, so as to improve data acquisition and processing speed, system reliability and inquiring efficiency.

The paper introduced a calculation method of grounding capacity current of high-voltage power network in coal mine,and gave a calculation of actual example.Using the method to calculate and analyze several coal mine power networks,the calculation results fit in measured results,which proved the calculation method is factual,simple,accurate,and is an accurate and valuable method.

In view of shortcomings of bad man-machine interface and less communication interfaces of monitoring device based on MCU,the paper put forward a design scheme of mine-used intrinsic ally safe industrial control computer based on ARM,and introduced design of hardware and software and extension methods of interface of the control computer in details.The practical application showed that the control computer is stable and reliable and has friendly interface.

In order to solve problems of complex wiring and high cost of existing wiring communication mode in mine fireproof grouting monitoring system,the paper proposed a realization scheme of remote communication of mine fireproof grouting monitoring system based on wireless bridge,introduced three link modes of wireless bridge and their characteristics of wireless communication,and expounded a scheme based on AX9800 11A wireless bridge and link mode of point to point,which realized remote communication function of fireproof grouting monitoring system of Jining No.2 coal mine.The test result showed that the scheme's valid distance of wireless communication is more than 10 km,valid transmission speed is 10 Mbit/s,and delay time of video signals is less than 5 s.Besides,the scheme has reliable transmission performance and perfect communication quality.

The paper introduced development of explosion proof video monitoring and control system of coal mine underground and analyzed existing problems of explosion proof video monitoring and control system of coal mine underground.It also designed a new explosion proof video monitoring and control system of coal mine underground.The system integrates computer technology,IP video technology,compress and decompress processing technology of video data and Internet application Internet technology,which realizes functions of real-time coding multicast and monitoring of remote video,remote camera and pan-tilt control based on point to point,point to multipoint,and multipoint to multipoint,and improves efficiency of video monitoring and control of coal mine underground.