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The paper puts forward a perception and alarm method of rock burst and coal and gas outburst based on temperature. The infrared thermal imager is used to monitor the temperature of objects, and the methane sensor is used to monitor the concentration of ambient methane. When the temperature of the objects is higher than the ambient temperature of the coal mine and the temperature of the exposed coal rock, and the number, volume and area of objects that are higher than the ambient temperature and the temperature of the exposed coal rock are large, it is determined that rock burst, coal and gas outburst, mine fire or gas and coal dust explosion accidents have occurred. The temperature of the high temperature object is further determine. If it is greater than the set threshold, it is determined that a mine fire or a gas and coal dust explosion accident has occurred. Otherwise, it is determined that a rock burst or a coal and gas outburst accident has occurred. The change of methane concentration is further analyzed. If the methane concentration rises rapidly, it is determined that a coal and gas outburst accident has occurred. Otherwise, it is determined that a rock burst accident has occurred. The paper puts forward a perception and alarm method of rock burst and coal and gas outburst based on velocity. The lidar, millimeter-wave radar, ultrasonic radar, binocular vision camera are used to monitor the moving speed of objects. The methane sensors are applied to monitor the concentration of ambient methane. When the moving speed of the object is not less than the set threshold, it is determined that rock burst, coal and gas outburst or gas and coal dust explosion accident have occurred. The number, volume and area of objects with abnormal velocity is further determined. If the number of objects with abnormal velocity is small, the volume and area are small, it is determined that a gas and coal dust explosion accident has occurred. If the number of objects with abnormal velocity is large, the volume and area are large, it is determined that a rock burst or a coal and gas outburst accident has occurred. The changes of methane concentration are further analyzed. If the methane concentration increases rapidly, it is determined that a coal and gas outburst accident has occurred. Otherwise, it is determined that a rock burst accident has occurred. A multi-information fusion method for perception, alarming and judging disaster source of rock burst and coal and gas outburst is proposed. The method monitors and integrates various information such as temperature, speed, acceleration, burial depth, sound, air pressure, wind speed, wind direction, dust, methane concentration, equipment status, micro-seismic, geosound, stress, infrared radiation, electromagnetic radiation and images so as to monitor the pressure and coal and gas outbursts. The source of the disaster is determined through the magnitude of parameter changes at different locations, the sequence relationship and sensor damage.

In order to reduce the number of operators in the working face of coal mines, an unmanned 5G ground remote control method for working face is proposed. The industrial cameras and sensors are set up in the working face, which transmit video, audio and sensor signals to the ground through the 5G network. The ground operator operates the equipment remotely, which transmits control commands to the working face through the 5G network, and controls the actions of the mine equipment. The wireless transmission distance and transmission bandwidth calculation method are proposed for unmanned ground remote control of the fully mechanized working face. The wireless transmission distance between the base stations at the two ends of the fully mechanized working face should not be less than 1/2 of the length of the fully mechanized working face. The total uplink transmission bandwidth required for unmanned ground remote control of the fully mechanized working face is proportional to the length of the fully mechanized working face, inversely proportional to the center distance of the hydraulic support, inversely proportional to the number of supports and cameras, and proportional to the transmission bandwidth required for the compressed video of a single camera. In order to reduce the demand for uplink transmission bandwidth for unmanned ground remote control of fully mechanized working face, it is possible to only transmit the camera videos of the adjacent shearers. The minimum bandwidth of uplink transmission required for unmanned ground remote control the fully mechanized working face is proportional to the number of cameras of the adjacent shearers, and proportional to the required transmission bandwidth of a single camera after video compression. The wireless transmission distance test method for the unmanned ground remote control system of the fully mechanized working face is proposed. The method is applied for the wireless transmission system such as 5G for the unmanned ground remote control system of the fully mechanized working face. Under the premise of ensuring transmission bandwidth, time delay and reliability, the wireless transmission distance is tested. The test shows that the uplink wireless transmission bandwidth of the base station shall not be less than 20 Mbit/s, and the wireless transmission distance shall not be less than 150 m. This study proposes the all-mine integrated information transmission network based on network hard slicing. Through network hard slicing, different channels are allocated for coal mine safety monitoring, mine monitoring, personnel and vehicle and equipment positioning, video monitoring, voice communication, 5G communication, etc. This method guarantees the high reliability and low time delay requirements of coal mine safety monitoring and mine monitoring, and unifies the underground information transmission network of coal mines. Moreover, it integrates multiple networks such as coal mine safety monitoring network, mine industrial Ethernet and mine 5G communication network.

In order to solve the problem that most of the current mine external fire monitoring methods do not have fire source positioning function, a binocular vision-based perception and positioning method of mine external fire is proposed. Firstly, the method sets up mine visible binocular cameras or near-infrared binocular cameras at multiple points in roadways, chambers and working faces with cables, tapes and electromechanical equipment to capture images of the monitoring area. Then, the adopted images are preprocessed and binarized images are obtained by threshold segmentation. The roundness, rectangularity and number of sharp corners in the image are calculated, and the images are identified by flames according to the roundness, rectangularity and number of sharp corners. If there is flame in the image detection area, a fire alarm signal will be issued and the temperature, smoke, carbon dioxide, carbon monoxide, oxygen and infrared sensor information are taken into consideration to improve the accuracy of alarms. Finally, the method uses mine visible binocular cameras or near-infrared binocular cameras to measure the distance of the fire source, locates the fire source based on the camera position, and outputs the fire source location information to control the fire extinguishing device near the fire source. Far-infrared binocular cameras can also be used for fire perception and fire source positioning, but the cost is high. The binocular vision-based perception and positioning method of mine external fire can sense and locate the fire source. This method has the advantages of wide monitoring range, low cost, fast response and visualization, and solves the problem of locating the fire source of mine external fire.

The characteristics of the mine wireless relay emergency communication system are analyzed in this study. The wireless transmission power is limited by explosion-proof, the mine wireless transmission attenuation is large, and the wireless transmission distance is short. The working frequency band is not limited on the premise that the wireless communication equipment working underground does not interfere with each other and does not affect the normal operation of the wireless equipment on the ground when being taken out of the mine. The relay links are distributed in a chain in the roadway, and the overall network is in a tree topology. In order to solve the impact of the broken cable (cable or optical cable) caused by the coal mine accident on the mine emergency communication system, the implementation method of mine wireless relay emergency communication system is proposed. This method separates the data transmission link from the protocol control link to improve the flexibility of link control and the transmission efficiency of routing protocol signaling. The receiving/transmitting frequency bands and sub-channel frequencies of each base station in the link are set according to the physical sequence of base stations, which solves the problem of mutual interference between relay stations at all levels. In data link relay transmission, each relay station in the link can exchange data continuously with the front and back nodes, which solves the problems of bandwidth loss, relay delay and system stability caused by multi-level relay. The frequency molecular channel mode of the relay station with spatial multiplexing of zones solves the problem of limited frequency division channel resources. The fixed node-based transparent routing strategy simplifies the level-by-level route addressing and route discovery process and improves data forwarding efficiency. The redundant base station down-link routing strategy of normal link avoids the channel interference problem caused by the mixed transmission of primary and redundant nodes. The link breakpoint recovery method of redundant base stations, mobile terminal bridging and local access coordination improves the anti-fault ability of the link.

In order to solve the problem that visible light images are greatly interfered by mine lights, car lights, roadway lights, dust and red object in mines, the mine external fire sensing method based on near-infrared and visible light images is proposed. The near-infrared images and visible light images are fused to bring into play the advantages of obvious early flame characteristics in near-infrared images and obvious mid-term flame characteristics in visible light images so as to improve the recognition rate of mine external fire. This paper proposes a mine external fire sensing method based on multiple information fusion of near-infrared image, visible light image, temperature sensor, gas sensor and smoke sensor. The method fuses near-infrared image, visible image and sensor information. The sensor does not need no blind area coverage. Only a certain number of gas sensors, temperature sensors and smoke sensors need to be set up, which has the advantages of being timely, reliable and low-cost.The fire alarms are divided into four categories, including the image, temperature, smoke and gas fire alarms. The image fire alarm information includes near-infrared image and visible light image information. When the fire is detected by near-infrared image or visible light image, the image fire alarm signal is issued.When the temperature exceeds the limit, the temperature alarm signal is issued. When the smoke exceeds the limit, the smoke alarm signal is issued. The gas fire alarm information includes CO, CO2, O2, etc. When CO, CO2 or O2 exceeds the limit, the gas alarm signal is issued. The fire alarms are divided into four levels, including blue, yellow, orange and red, with red being the highest level.When one of the four alarm signals of image, temperature, smoke and gas issued, the blue alarm signal is issued. When two of the four alarm signals of image, temperature, smoke and gas issued, the yellow alarm signal is issued. When three of the four alarm signals of image, temperature, smoke and gas issued,the orange alarm signal is issued. When all four alarm signals of image, temperature, smoke and gas issued, the red alarm signal is issued.

Xin He,1 Jiping Sun,2 Chao Liu,2 Xiaoyang Yu,2 Huixian Li,2 Wenjing Zhang,2 Yan Li,2 Yingzhou Geng,2 Zhigang Wang2 1Dialysis Department of Nephrology Hospital, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of China; 2Department of Nephrology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of ChinaCorrespondence: Zhigang Wang, First Affiliated Hospital of Xi’an Jiaotong University, West Yanta Road 277, Xi’an, 710061, People’s Republic of China, Email wangzhigang2017@xjtu.edu.cnPurpose: Emerging evidence has revealed that gut microbiota plays a pivotal role in the pathogenesis of type 2 diabetes mellitus (T2DM) and diabetic kidney disease (DKD). However, few studies have used metagenomic sequencing to analyze the alterations of gut microbiota community in patients with early-stage DKD.Methods: We carried out metagenomic sequencing in fecal samples of 10 DKD patients (DKD group) and 10 T2DM patients who appeared to be less prone to DKD (non-DKD group), aiming to compare the composition and function of gut microbiota between the DKD and non-DKD groups.Results: The gut microbial community of the DKD group was significantly different from that of the non-DKD group, characterized by a marked increase in phylum Proteobacteria, genus Selenomonadales, Neosynechococcus, Shigella, Bilophila, Acidaminococcus, species, Escherichia coli, Bacteroides plebeius, Megasphaera elsdenii, Acidaminococcus unclassified, and Bilophila wadsworthia. The amounts of species Citrobacter farmeri and Syntrophaceticus schinkii were significantly and positively correlated with the urinary albumin creatinine ratio in the DKD group. Furthermore, functional analysis based on dbCAN and KEGG databases showed aberrant lipopolysaccharide (LPS) biosynthesis and carbohydrate metabolism in the gut microbiome of the DKD group.Conclusion: Our findings provided evidence for alterations in the composition and function of gut microbiota in patients with DKD versus the non-DKD group. These data may contribute to a more comprehensive understanding of the pathological mechanisms of DKD.Keywords: diabetic kidney disease, gut microbiota, metagenomics, type 2 diabetes mellitus

This invited Editorial addresses the rescue of the article by Xue et al. "Hydrogen sulfide treatment promotes glucose uptake by increasing insulin receptor sensitivity and ameliorates kidney lesions in type 2 diabetes." The work was rejected by the standard peer review system and subsequently rescued via the Rebound Peer Review mechanism offered by Antioxidants and Redox Signaling (Antoxid Redox Signal 16: 293-296, 2012). The open reviewers rescuing the work were Jin-Song Bian, Samuel Dudley, Hideo Kimura, and Xian Wang. The initial article was reviewed by six reviewers who had valid concerns; they recommended extensive revision and additional experiments. In the subsequent two iterations, the authors nearly doubled the number of experiments and made substantial revisions. However, several reviewers were still not satisfied, and the authors requested the rebound pathway. The open reviewers, selected by the authors and experts in hydrogen sulfide biology, diabetes, and cardiovascular physiology, added a broad perspective to the review process. They acknowledged the anonymous reviewer's concerns, but felt that the merits of the study were sufficient to recommend acceptance. The open reviewers also identified several situations where the recommendations of the anonymous reviewers and the author's attempts to rectify them were moot, given the available methodology and present state of the field. From this perspective, the rebound track was a success; it rescued an article that otherwise would have been rejected and will stimulate further discussion and research in this area. Whether or not there are more efficient ways to accomplish, this remains to be determined.

A network survivability analysis model of Mine Ethernet Passive Optical Network (M-EPON) system in the mine communication was proposed, the topologies of dual-bus and dual ring-shaped network were presented. Also, the network survivability of the traditional tree-shaped and above proposed two different topologies of M-EPON systems was studied respectively. Simulation results show that the survivability of proposed structure is better than that of the traditional tree-shaped structure, and the dual-bus and dual ring-shaped network structure are further to enhance robustness and availability of M-EPON system.

Simulating characteristics of human intelligent, a new intelligent controller was produced: human-simulation logical predictive controller (HLPC). This controller can utilize the advantage both in logical controller based on pan-boolean algebra and model-based predictive controller. It is a multi-logic hybrid dynamic system. Simulated results based on Matlab prove that HLPC shows good performance when predictive model matches and satisfactory results when model mismatches, represents better robustness and small overshoot . Compared with other artificial intelligent controller, HLPC has simple structure, clearly physics background and mathematical concepts, thus would make it easy for industrial application.

Stringing haulage motors were main underground conveyance equipments, but they were the strong electromagnetic interference sources. To resolve the problem of monitor system false alarm and mobile communication interruption, the interference generation mechanism and distribution characteristic were analyzed. The means of conducted interference circuit analysis and stray current quantitative analysis were adopted. The radiated interference of the stringing haulage motor was measured with Protek3201 field-intensity meter at the second mine of Pingdingshan coal Co. Ltd. The conducted interference, stray current and radiated interference were the main factors of gas monitor and mobile communication malfunction. The anti-interference measures were taken, which included the power supply isolation, equipotential earth and shield to radiated interference. Results indicate monitor system false alarm and mobile communication interruption have been eliminated completely. It is concluded that the electromagnetic compatibility of underground gas monitor and mobile communication has been enhanced evidently with these anti- interference measures.