Abstract: A method is to excavate main roadways in the upper and lower parts separately and an inclined intake roadway in the central part of the mine and pre-excavate an inclined seam roadway as the first mining face at the boundary on one side of the mine. Staring from the mine boundary, the retreating mining shall be carried out on the first mining face strip by strip with belt conveyors arranged in the upper main roadway and assistant conveying devices in the lower main roadway and inclined intake roadway; the open-off cut of the first mining face shall be built on the underside of the upper main roadway at the boundary of the mine to carry out the downward inclined mining on the strike and along the inclination.

Abstract: A self-propelled towing simulator for a hydraulic lift system carries a gyro pose control system and a six-degree-of-freedom (DOF) platform to control the overall pose of the simulator, so that the simulator simulates six-DOF motion states including swaying, surging, yawing, rolling, pitching and heaving generated by a mining vessel under the combined action of waves and flows and required by the experimental working conditions; interventions in the pose of the simulator may be positive or negative, so that the simulator may be applied to the uncontrollable natural water bodies so as to approximate to the working conditions of the experimental requirements. The simulator may carry out experiments in open natural water bodies by use of its own autonomous sailing capability under remote wireless control and may acquire parameters such as dynamic characteristics and spatial configuration and the like of a deep-sea mining hydraulic lift subsystem in real time.

Abstract: An in-situ test device and method for surrounding rock strength of bolt supported roadway is provided. The test device includes a fixing mechanism, a loading mechanism, a measuring mechanism and a control system. The loading mechanism includes a hydraulic pump and a plunger pump, the hydraulic pump drives the plunger pump to work and controls the lifting speed of the loading cylinder; the measuring mechanism includes an infrared ranging unit and a wireless pressure monitoring unit; the control system controls the work of the loading mechanism and processes the monitoring data. The test device is directly installed in the roadway and fixed with the bolt. The device is loaded after leveling, the device is disassembled after the monitoring data are obtained, and the in-situ test for the surrounding rock strength of the bolt supported roadway is completed. The steps are simple and adaptable.

Abstract: Provided is a multi-functional plugging agent for a coal mine and a preparation method thereof. The preparation method comprises: by taking Ecklonia Kurome Okam as a raw material, mixing an Ecklonia Kurome Okam suspension with phosphorus pentoxide for reaction, then performing biodegradation to obtain an Ecklonia Kurome Okam biological extract, adding urea for neutralization, mixing a neutralization product with an inorganic catalyst and melamine for reaction to obtain a bio-based plugging synergist solution, finally cooling the bio-based plugging synergist solution, and mixing the cooled bio-based plugging synergist solution with a certain amount of pentaerythritol and ammonium polyphosphate to obtain the multi-functional plugging agent for the coal mine based on the Ecklonia Kurome Okam biological extract.

Abstract: A photothermal seawater desalination material with a multi-stage structure and a preparation method and application thereof. The photothermal seawater desalination material includes a light-absorbing material having a C/WO3-x heterogeneous junction, which is obtained by depositing a nano-C material on a porous metal foam material using plasma enhanced chemical vapor deposition (PECVD), and then synthesizing WO3-x with plasma resonance effect by a solvothermal reaction.

Abstract: The present invention provides a method for realizing high stability of micro-nano optical fiber sagnac loop output by means of filter mode control, and belongs to the field of photoelectric detection technologies. In the present invention, the optical filter is combined with the micro-nano optical fiber Sagnac interference structure so as to control the Sagnac in-loop working mode by use of the mode selection characteristics of the filter. In this way, the interference mode is suppressed to better concentrate energy on the working mode, thereby improving the spectrum output uniformity and stability of the Sagnac loop. Further, the reflection and transmission modes of the optical filter do not participate in interference spectrum output and thus the performance of the system will not be affected. By designing and changing the parameters of the optical filter, the output characteristics of the interferometer can be dynamically controlled.

Abstract: An experimentation method for a type I stress intensity factor test considering frost heaving force periodic changes, steps being 1: preparing a specimen, waterjet cutting on the specimen to simulate a non-penetrating rock mass fracture; step 2: vacuum saturating the specimen; step 3: affixing a strain gauge in a non-elastic area at a tip of the specimen; step 4: placing the specimen into a rock mass (1) fracture frost heaving experiment box (5), pressurizing by a pressurizing apparatus (4) balloons on either side of the frost heaving experiment box (5), shutting a valve and removing a pipe, placing the frost heaving experiment box (5) holding the specimen into a water tank, allowing water to immerse the specimen; and step 5: placing the water tank and the frost heaving experiment box (5) holding the specimen together into a high-low temperature alternating experiment box (7) to start a freeze-thaw cycle experiment.

Abstract: Disclosed is an unmanned food delivery device in a cabin. The device comprises a first conveying mechanism, a second conveying mechanism and a loading and unloading mechanism. The first conveying mechanism comprises a universal conveyor belt, and the universal conveyor belt is driven by universal wheels to convey lunch boxes, and the universal conveyor belt is used for conveying lunch boxes in a kitchen area and a passenger area in a reciprocating manner; multiple second conveying mechanisms are respectively arranged on a luggage rack bottom plate in the passenger area, the luggage rack bottom plate is provided with multiple feeding openings respectively corresponding to seats at intervals, each second conveying mechanism is respectively positioned at the feeding openings, the second conveying mechanisms are connected with the first conveying mechanism and used for conveying lunch boxes by the first conveying mechanism to the seats.

Abstract: An anti-impact device includes a first connector, an upper outer cylinder, a lower outer cylinder and a second connector which are sequentially connected, where a top of the lower outer cylinder is sleeved with the upper outer cylinder to be movably connected to the upper outer cylinder; an aluminum honeycomb and a magnetorheological buffer outer cylinder are arranged inside the lower outer cylinder, the aluminum honeycomb is arranged at a bottom of a lower end cover, a piston rod is arranged inside the magnetorheological buffer outer cylinder, a top end of the piston rod extends out of an upper end cover and is connected to a collision head, and the piston rod between the collision head and the upper end cover is sleeved with a return spring; and an electromagnetic coil is wound around the piston rod, a damping piston is arranged at a lower part of the piston rod.

Abstract: An intelligent optical fiber tactile sounding system and a method thereof, and belongs to the field of intelligent optical fiber sensing. The system includes a flexible optical fiber tactile sensing array, a photoelectric detection system, an intelligent pressure analysis software and an acoustic emission system; a small-scale distributed tactile sensing array is constructed by embedding a fiber-core mismatched optical fiber interferometric sensor into a flexible substrate material and performing sensing region division for an asymmetrical structure with an optical fiber structure as a delimiting line; a tactile sensor transmits tactile signals to the photoelectric detection system in the form of optical signals, the photoelectric detection system inputs these pressure signals into the intelligent pressure analysis software to determine a region and a size of a tactile source, and then sends an instruction to the acoustic emission system to enable the acoustic emission system to emit different sounds.

Abstract: The disclosure discloses an automatic simulation test bench and a test method for similar materials of top-coal caving mining. Wherein, the test bench includes a test bench base, a coal seam and strata simulation module, a coal releasing simulation module, a material recovery module, automatic mixing system and a central control system. The disclosure adopts modular construction to meet the requirements of similar material simulation test of top-coal caving mining under different geological conditions and mining technology to the greatest extent. The disclosure adopts automatic control, reduces the working intensity and operation difficulty of the test personnel, and reduces the influence of human factors on the test results. The disclosure adopts a lifting structural design, so as to meet the requirements of similar simulation test of top-coal caving mining under different mining and caving ratios.

Abstract: A method for producing a dust-reducing and dust-absorbing material from a nonmetallic mineral and a raw material from a cement plant. The method includes calcining the limestone block, to obtain quicklime; cooling the quicklime at ambient temperature, drying and pulverizing the quicklime, to obtain a first powder essentially consisting of a quicklime powder and a calcium carbonate powder; fully drying and grinding a nonmetallic mineral, to obtain a nonmetallic mineral powder; mixing the first powder and the nonmetallic mineral powder, stirring to be uniform, to obtain a mixture, and ball milling the mixture, to obtain a nano-powder; adding a dust-absorbing material to the nano-powder, adding water and mixing, and pouring the resulting mixture into a mold, and stoving; and air drying the resulting mixture, to obtain a cavernous dust-reducing and dust-absorbing material.

Abstract: A deep low-permeability gassy seam drilling-slitting-sealing-fracturing drilling device includes a drilling control system, a high-pressure water power system, a water pressure grading control system and a fracturing and sealing control system. The drilling control system adjusts a drilling direction a water supply pressure of the drill rod, the high-pressure water power system supplies high-pressure water with different pressures to the device, and the water pressure grading control system ensures that a water pressure for flushing drill cuttings is less than 5 MPa, a water pressure for slitting in a direction perpendicular to a length of the drill rod is 25-35 MPa, a water pressure for sealing with a borehole sealing capsule is 35-40 MPa, and a water pressure for further pressure relief and permeability increasing of a coal seam is 40-50 MPa. The fracturing and sealing control system controls borehole sealing and hydrofracturing operations.

Abstract: The present invention discloses a deformation controllable compression ring-based mechanical test system for rocks with variable stiffness and a test method thereof, which comprises a loading device, a variable stiffness regulating device, a data monitoring system and a controlling system; the energy storing spring in the loading device allows the rebounding direction of the loading device to be contrary to the strain direction of the test-piece, which eliminates the energy supplement of the loading device to the test-piece and realizes the loading of an oversized stiffness on the test system; the variable stiffness regulating device precisely regulates the loaded stiffness by regulating the loaded stiffness of the test system according to test requirements, which realizes the test of loading different stiffness on the same test system and avoids the influences of differences to loading parameters between different test systems on the test results.

Abstract: The present invention relates to the technical field of high-gain DC-DC converters, and disclosed is a high-gain quasi-resonant DC-DC converter based on a voltage doubling rectifier circuit. On the basis of a half-bridge quasi-resonant high-gain circuit topology and by combining a bidirectional positive and negative voltage doubling rectifier circuit, the present invention provides a high-gain DC-DC converter. The converter can further improve output voltage gain and reduce output voltage ripples, and can improve the system efficiency while reducing the number of turns of a high-frequency transformer; moreover, the converter can achieve soft-switching control, thereby having the advantages of low voltage and current stress, high efficiency, and the like.

Abstract: Disclosed is a magnetically controlled material-based magnetorheological pilot operated safety valve for a hydraulic support. The safety valve comprises a valve body, a valve core, a reset spring, and a pilot valve; the valve core is disposed in a valve core chamber provided in the valve body, and the pilot valve is disposed in a pilot valve chamber provided in the valve body; the pilot valve includes a magnetically controlled shape memory alloy, an electromagnet, a push rod, a piston, a magnetorheological fluid control coil, and a pilot valve core, which are arranged sequentially from left to right; a plurality of magnetically controlled material control coils are provided on the electromagnet; the magnetically controlled shape memory alloy runs through the electromagnet and is then connected to the push rod, the push rod is connected to the piston, the magnetorheological fluid lies between the piston and the pilot valve core.

Abstract: A system for navigation detection and inclination measurement of advanced hydraulic supports, including a detection device module, a signal transfer transmission module, connected to the detection device module, and used to integrate ultrasonic signals and inclination signals received from all advanced hydraulic supports and then wirelessly transmit all the signals to an analysis and processing module. The analysis and processing module, connected to the signal transfer transmission module, and used to receive the signals from the signal integration and transmission device for analysis, where if an analysis result shows an abnormal situation, an alarm will b e immediately given to a worker. If the analysis result shows a continuous abnormal situation, or a relatively large value indicating the abnormal situation is generated, a command will be immediately sent to make the advanced hydraulic supports stop operating in a current mode.

Abstract: A system and method for monitoring crack propagation of a transparent rock specimen monitors a breakage process of a specimen loading process. In the system and method for monitoring crack propagation of a transparent rock specimen, under the condition of no contact with a rock specimen, intensity changes of laser light passing through the transparent rock specimen in a loading state are determined, such that a computer (5) forms, according to laser intensity change data, a three-dimensional diagram of crack propagation of the transparent rock specimen (4) in a continuously loaded state at a plurality of set time points. This is used to analyze a breakage starting point and a crack propagation path and process of the transparent rock specimen (4) in the loading state, and achieve the purpose of qualitative analysis of the rock specimen.

Abstract: Terahertz spectrum measurement method and system based on an unequal optical path method is provided. By using a Femtosecond laser and a Terahertz time-domain spectroscopy system, samples to be measured and having different thicknesses are subjected to scanning by time-domain Terahertz signals to obtain transmission signals of the samples with two different thicknesses. The signal after passing through a sample with the thickness of d1 is a reference signal, and the signal after passing through a sample with the thickness of d2 is a sample signal. When Terahertz waves are normally incident to the samples and having different thicknesses, the signals emitted from the samples have an optical path difference therebetween. Phase-containing frequency spectra are obtained after time-domain signals are subjected to Fourier transform. The parameters, such as a refractive index, an extinction coefficient, and an absorption coefficient, can be calculated through the extracted phase-containing frequency spectrums.

Abstract: A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.