139results about How to "Reduce the impact of disturbance" patented technology

The invention discloses a method for classifying electric energy quality mixed disturbances based on multi-feature quantity of time-frequency domain. Voltage dip, voltage swell, short-term voltage interruption, impulsive transient, oscillatory transient, harmonic waves and flickering electric energy quality disturbances and mixed disturbances of a combination thereof are classified. The method for classifying the electric energy quality mixed disturbances concretely comprises the steps of: firstly, processing a disturbance signal by using an EEMD (Ensemble Empirical Mode Decomposition) and MIST (modified incomplete S-transform), and extracting nine time-frequency domain characteristic values; and then, inputting characteristic quantity to a blocked automatic classifying system to recognize the disturbances. By using the method, the mutual interference among single disturbances is fully considered and is effectively inhibited through the complementary time-frequency domain characteristic values. A simulation result shows that, under conditions of certain noises, the method can be used for effectively classifying the voltage dip, the voltage swell, the short-term voltage interruption, the impulsive transient, the oscillatory transient, the harmonic waves and the flickering electric energy quality disturbances and the mixed disturbances of the combination thereof.

The invention relates to a control method, in particular to a control method for an automotive active suspension system. The problem that design models are simple, and single-target control is mainly adopted in the conventional suspension control technologies, so that external uncertain disturbance and unmodeled dynamics cannot be coped with is solved. The control method specifically comprises the following steps of: establishing a nonlinear active suspension model; designing a nonlinear robust controller; and regulating gains k1, k2, epsilon1 and epsilon2 to ensure that all constraints are limited within a permissible range, namely to realize constraint control. The control method is used for the control and the stabilization of the automotive active suspension system.

The invention discloses a touch screen and a driving method thereof. The touch screen is characterized in that touch electrodes are internally embedded in a display panel; the touch electrodes comprise a touch signal input electrode and a touch signal output electrode, which are crossly arranged in an insulating manner; a first common electrode is at least divided into a plurality of regions along the direction of data lines; each region of the first common electrode corresponds to at least one row of pixel units; and all regions of the first common electrode are insulated to each other and serve as the touch signal input electrode. According to the touch screen disclosed by the invention, the common electrode is divided into the plurality of regions along the direction of the data lines, and the regions serve as the touch signal input electrode. According to the invention, the reduction of a pixel voltage is offset by voltage disturbance produced when the common electrode is used as a driving electrode so that the disturbance influence caused by the scanning of the common electrode is reduced and the quality of displayed pictures is increased.

The invention discloses an underground station constructed by prefabricated parts and a construction method thereof. The underground station comprises an upper station layer and a lower station layer; the upper station layer and the lower station layer are both formed by assembling a plurality of prefabricated parts, the lower station layer is communicated with the upper station layer, upper and lower station layer stairways are arranged at the communicating position, and the lower station layer is provided with a platform; the upper station layer is communicated with the ground, and a plurality of ground stairways communicated with the ground are arranged in the upper station layer. The lower station layer and the upper station layer are constructed in sequence, stiffening rib steel structures are dismantled after assembly of the prefabricated parts is completed, and an underground station space structure is formed; a top plate of the lower station layer and a bottom plate of the upper station layer are connected through bolts, pouring and leveling treatment is performed on bottom plates of the two layers, combined structure columns in the station are bound, and concrete is poured for reinforcement; then the station is decorated to complete station construction. The method has the advantages that construction is flexible and rapid, small-buried depth construction can be performed, influences on traffic and environment are small, and industrial production can be achieved.

The invention provides a high-precision double star laser interference dynamic distance measuring ground simulation device which at least comprises a vibration-isolation system, a vacuum system, a light source system, an interferometer, a first horizontal moving system, a second horizontal moving system, a phase detection system and a data analyzing system. The vibration-isolation system is used for isolating and filtering outside vibration noise and reducing the vibration noise of a system. The vacuum system is used for reducing thermal noise brought by temperature fluctuation of the system. The light source system is used for providing two laser beams which are high in stability and high in frequency stabilization. The interferometer is used for generating three paths of heterodyning interference signals which have the identical arm length and simulating satellite orbit dissociating motion information and scientific signal information caused by gravitational waves or a gravitational field or the like. The first horizontal moving system is used for simulating scientific signals caused by gravitational waves or a gravitational field or the like. The second horizontal moving system is used for simulating satellite orbit dissociating signals. The phase detection system is used for carrying out phase detection on interference signals, collecting phase information and carrying out inversion displacement. The data analyzing system is used for estimating dynamic distance measuring precision of an interfering system and extracting scientific signals from mixed signals. The high-precision double star laser interference dynamic distance measuring ground simulation device can achieve ground simulation of high-precision double star laser interference dynamic distance measuring.

The invention discloses a contour error controller for a multi-axis motion system and a control method thereof. The contour error controller comprises the multi-axis motion system. Each axis of the multi-axis motion system is provided with a sliding mode variable structure controller and an extended state observer. The sliding mode variable structure controller can obtain a control signal based ontracking errors of each axis; and the extended state observer can observe observation variables for producing position signals, velocity signals and disturbance signals of each axis. The invention proposes a contour error control algorithm based on extended state disturbance observation for multi-axis linkage control system formed by three-axis permanent magnet linear synchronous motor servo drives, thereby effectively reducing tracking errors and contour errors. The extended state observer is used to observe the disturbance signal to reduce influence of the disturbance, and a sliding mode variable structure control algorithm is combined to form a uniaxial trajectory tracking controller, thereby ensuring uniaxial tracking accuracy and robustness; and through a cross coupling controller, the problem of multi-axis coordinated movement is solved and multi-axis contour control precision is improved.

The invention discloses a uniaxial laser gyro north seeker and a north-seeking method thereof. The north seeker comprises a mechanical rotating cabin and an electronic cabin, wherein the mechanical rotating cabin comprises a prism-type digital laser gyroscope, an inclinometer, a rotating cabin secondary power source and a uniaxial rotary table; the electronic cabin comprises a calculation computer, a rotary table controller, an Ethernet converting circuit and an electronic bin secondary power source. The north-seeking method comprises two steps, namely a coarse north seeking step and a fine north seeking step, in the coarse north seeking step, a three-position north seeking method is adopted, and in the fine north seeking step, a two-position north seeking method is adopted. The north seeker provided by the invention can realize functions of high north seeking precision, low power consumption, short north seeking time, high reliability, low cost, and small size under a vehicle-mounted environment, has an anti-interference ability, and can complete north seeking in case of base disturbance caused by blowing, people walking, engine vibration and the like.

The present invention relates to a vehicle trajectory prediction method and device based on the driver's control intention, and a system. The invention comprehensively considers the driving intentionand the real-time motion state of an automobile to make short-term predictions on the trajectory, speed and acceleration parameters of the automobile, and reduces the disturbance influence of driver'scontrol behaviors on the prediction of the automobile motion state. The method is easy to implement, has low algorithm complexity, is widely used in driving simulators, automobile collision hazard early-warning, and automobile safety assisted driving systems, and is used to evaluate and predict trajectory crossing between moving vehicles and the collision risk.

A space stealth flight technical method comprises an infrared stealth technology, an antiradar stealth technology, an anti-visible light stealth technology, and an anti-laser detection technology. The infrared stealth technology adopts a space cold shielding system near triple point refrigeration technology mainly comprising a ground filling up process, a ground pressure filling up process, a starting process and a steady-state flight process, each process is implemented by a layered liquid storage method, a saturated vapor outlet pipe diffusion diversion method, a cold vapor emission control method and a superheated vapor secondary diffusion diversion method. The inventive method integrally utilizes the anti-infrared, anti-radar, anti-visible light, anti-laser detection technologies and other technologies of space aircrafts, and enhances the full-dimensional space stealth flight ability of the aircrafts, so as to meet the space safety flight requirements; and is especially suitable for the safety stealth flight of the space aircrafts.

The invention discloses a detection device and detection method for measuring long-focal-length lens transmission wavefront by a computer-generated holography, and belongs to the technical field of optical measurement. The detection device is mainly characterized in that an interferometer, a measured long-focal-length lens and a Fresnel wave zone plate form a Fizeau interference optical path; when collimated parallel light output by the interferometer passes through a standard plane mirror, one beam is reflected by a reference surface of the standard plane mirror to form a standard reference light beam; the other beam penetrates through the measured long-focal-length lens to be transmitted and is reflected through the wave zone plate to return along the original path for forming a test light beam; the test light beam and the standard reference light beam generate interference; the tested long-focal-length lens is regulated, so that interferometric fringes are minimum; the transmission wavefront of the tested long focal-length lens can be obtained through measurement. The method and the device provided by the invention are applicable to the detection of the long-focal-length lens transmission wavefront.

The invention discloses a landslide and slope governing non-vertical type antiskid pile structure and an installation method. The method includes the steps that collecting and investigating are conducted on the physical mechanical parameters of the landslide type, the scale, the landslide mass thickness, the landslide perimeter, the sliding face type, the sliding face space position, a sliding main shaft and a rock-soil body in the landslide affection range according to reconnaissance data; landslide thrust calculation is conducted according to a mechanical model recommended by current specifications based on the data obtained through collecting and investigating; and design of geometrical parameters such as the pile length, the pile body anchorage section length, the pile interval and thepile body section size is conducted according to the landslide thrust obtained through calculation; non-vertical type antiskid piles and the rock body in the landslide affection range are rotated into vertical type antiskid piles according to the preset angle, then pile body internal force calculation is conducted, and reinforcement is conducted on the non-vertical type cast-in-place concrete antiskid piles; and construction is conducted according to the designed geometrical parameters and reinforcement. By means of the landslide and slope governing non-vertical type antiskid pile structure and the installation method, a lot of money can be saved in the landslide and slope governing process, the construction period is shortened, and meanwhile environment protection is facilitated.

The invention relates to a forcer / position hybrid control method of a multi-arm teleoperation robot based on a performance function. The situation that the force / position coupling of an operation object and mechanical arms in the operation process in the actual operation process is considered, by correspondingly designing controllers of a master terminal and a slave terminal, in the control process of the slave terminal mechanical arm, by pre-designing the performance function of the mechanical arms, a force position hybrid controller of the slave terminal mechanical arm is designed, so that under the condition that a target is disturbed by certain external factors in the operation process, the influence of disturbance can still be reduced through the control of the mechanical arms, and the position, speed and acting force of the robot can be adjusted adaptively at the same time to ensure the stability of system operation, and thus the cooperative operation of multi-arm teleoperation is realized.

The invention discloses a flapping-wing aerial vehicle driven by steering engines and a flapping-wing aerial vehicle driving method. The flapping-wing aerial vehicle comprises steering engine structures, a flight control panel and a body, wherein the steering engines are used for controlling motion of left and right wings; the flight control panel is used for realizing the wireless communication function between the steering engines and a remote control and realizing motion control of the flapping-wing aerial vehicle according to a flight instruction of the remote control via the steering engines. The steering engines are taken as the driving mode for controlling wing motion, the two steering engines are used to replace a conventional driving mode of a motor and a gear set, the left and right wings of the flapping-wing aerial vehicle are independently controlled, the controllable amount comprises the flapping amplitude, the flapping frequency and the initial position of each wing, multiple flight gestures including straight flight, circling, steering and the like of the flapping-wing aerial vehicle are realized, the driving mechanisms of the flapping-wing aerial vehicle are reduced, the driving efficiency is improved, the flapping-wing aerial vehicle is easy to operate, and stable flight and steering control can be realized.

The invention discloses a preparation method of a silicon epitaxial wafer for a high-voltage power device. According to the method, a reaction cavity of the epitaxial equipment is purified and the content of impurities accumulated in the cavity is reduced by long-time purging of large-flow hydrogen before epitaxial growth; the nonlinear gradient heating is adopted, so that the stress accumulated in the heating stage is released in time, and the generation probability of defects is reduced; and the reaction rate is significantly improved by shortening the distance between a quartz bell jar anda base of the reaction cavity of the epitaxial equipment and adopting a large-flow trichlorosilane and hydrogen proportioning mode, and high-speed epitaxial growth is realized under the premise of ensuring good crystallization quality of the silicon epitaxial wafer. The problem of comprehensive control on thickness, resistivity and crystallization quality in the existing preparation process is overcome by adopting the method of sectional growth of the silicon epitaxial wafer layer. the prepared silicon epitaxial wafer has a bright surface, is free from dislocation, staggered layers, slip linesand fog defects, realizes the controllability of material indexes such as thickness, resistivity and defects and meets the use requirements of the high-voltage power device.

The invention provides a coal mine deep vertical shaft disturbance-resisting ingate structure. An ingate comprises a first pouring section, a second pouring section, an auxiliary chamber and disturbance influence separation holes. The first pouring section is the first part to be constructed on the two sides of a shaft, and is poured integrally with a shaft wall. The second pouring section is arranged behind the first pouring section, a separation seam is formed between the first pouring section and the second pouring section, a foam plastic plate is arranged in the separation seam, the disturbance influence separation holes are formed in the first pouring section located on one side of the separation seam, and a shake station foundation is arranged under the auxiliary chamber. The first pouring section is lengthened, and disturbance influence of the second pouring section which is constructed subsequently on the near shaft wall is reduced. In addition, through the disturbance influence separation holes, the disturbance influence of the second pouring section which is constructed subsequently on the first pouring section and the near shaft wall is separated, and the coal mine deep vertical shaft disturbance-resisting ingate structure has wide practicability and operation ease.

The invention relates to a static flotation column suitable for coarse particle recycling, belongs to the technical field of mineral flotation and solves problems of unstable running, poor adaptability, small processing capacity, poor separation effect and failure to meet requirements on coarse particle slime recycling of the existing flotation column. The static flotation column comprises a firstcolumn body and a second column body; each of the first column body and the second column body is of a barrel-shaped structure; the upper part of the second column body penetrates after passing through a bottom plate of the first column body and is hermetically nested in the first column body; a feeding distributor is arranged in the space from a top opening of the second column body to a top opening of the first column body; the feeding distributor is connected with a feeding pipe; a water distribution pipe connected with a flush water pump is arranged above the feeding distributor; an overflowing groove is formed in the upper outer periphery of the first column body; and the bottom of the first column body is connected with the bottom of the second column body by a flowing guiding pipeto form a fluid circulation loop. The flotation column disclosed by the invention is stable to run, good in separation effect, and capable of being widely applied in coarse particle coal slime recycling.

The invention discloses a construction method enabling a shield tunneling machine to underneath pass through an existing station to start. A steel sleeve is adopted for construction, and the followingflow including bottom plate levelling and steel plate laying for an underneath passing channel, vertical freezing reinforcement for a tunnel door, installation for the lower half-circle of the steelsleeve, downhole installation for the shield tunneling machine, overall underneath passing and longitudinal movement of the steel sleeve, breaking for the tunnel door, installation for a negative ring, backfilling for the sleeve, pressure testing, pulling-out for a freezing pipe, sealing for a freezing hole, and starting of the shield tunneling machine. The steel sleeve comprises a main sleeve body, a transition ring, a reinforcing ring, a bottom frame and a counter-force frame, wherein the main sleeve body is formed by splicing four sections of sleeve bodies with the same length; and each sleeve body is composed of an upper half-circle sleeve body and a lower half-circle sleeve body. The transition ring is connected to the front end of the main barrel body; the reinforcing ring is connected to the rear end of the main barrel body; the bottom frame is also divided into four sections of bases; and the counter-force frame is connected to the rear end of the reinforcing ring. According tothe construction method, damage to a constructed station structure can be avoided, the construction risk and difficulty of starting driving of the shield tunneling machine and later-period detachmentfor the sealing device for the tunnel door are lowered, and the construction period is accelerated.

The invention discloses a construction method of an open caisson. The construction method comprises the steps of construction preparation work; foundation pit excavation as well as sand cushion layerand plain concrete cushion layer manufacturing; open caisson first-section, open caisson second-section and open caisson third-section manufacturing; open caisson first-time sinking; open caisson fourth-section and open caisson fifth-section manufacturing; open caisson second-time sinking; open caisson underwater plain concrete bottom sealing; open caisson bottom plate manufacturing; and pipelinebuttress, mud discharging well and tail work construction. The open caisson sinks by adopting an undrained process, the soil sampling mode is matched with an air mud suction diver, and the sinking assisting mode is sinking by a pressure sinking method and resistance reduction and sinking assisting by thixotropic mud. According to the method, the sinking method is adopted, the posture of the open caisson is convenient to control, the sinking precision of the open caisson is high, the depth of open caisson blade feet penetrating into a soil layer is larger through a counter-force system, the sufficient sinking coefficient is achieved, the sinking speed of the open caisson can be greatly increased, disturbance to external soil is small, the phenomenon that a structure is prone to differentialsettlement, deformation, cracking and the like are effectively prevented, and a soil bin in a well lattice cannot be raised in the sinking process.

The invention discloses a power quality compound control device based on a nine-switching tube inverter. The main circuit structure of the device based on the nine-switching tube inverter provides twooutput ports, the output port at the upper end is connected to a grid in series through a coupling transformer to achieve the function of a dynamic voltage restorer (DVR), and the output port at thelower end is directly connected to the grid in parallel to achieve the function of an active power filter (APF). The DVR port controls output voltage by means of a load control strategy based on gridvoltage feedforward and load voltage feedback, so that voltage sag and three-phase imbalance are compensated for rapidly and accurately. The ARF port detects a harmonic current by means of an improvedFBD method based on an averaging method and a phase-leading network, and controls an output current by means of multiple quasi-PR control, so that detection and compensation of the harmonic current,an unbalanced current and a reactive current are completed rapidly and accurately. The power quality compound control device based on the nine-switching tube inverter has the advantages that three switching tubes are saved, the production cost is reduced, the installation flexibility of the device is improved and the application field is broadened.

The invention discloses a hot steam re-extraction heat supply control system and method coupled with a pressure matcher. A multi-nozzle needle valve is coupled to control the pressure matcher, and the flow and pressure of an outlet of the pressure matcher are adjusted by adjusting the opening of the needle valve; meanwhile, two controllers which are connected in series to work are selected to form a double-closed-loop control system, an auxiliary controller is used for performing advanced control on desuperheating water interference, and the influence of the desuperheating water interference on the outlet steam temperature is reduced; and meanwhile, according to a double-closed-loop system, temperature setting feedforward of driving steam is obtained in advance, the disturbance influence caused by parameter changes of the driving steam and suction steam due to working condition changes of a unit can be weakened, and control is more accurate. The problems that the delay of the outlet steam temperature of the pressure matcher and the time constant are very large, the interference effect of desuperheating water is strong and frequent, and the parameter change of driving / suction steam due to the change of working conditions is difficult to accurately control are solved.

The invention discloses a shield tunnel synchronous grouting similar model testing method. A test box, a data acquisition system connected to the top surface of the test box, a construction simulationsystem penetrating through the test box, a grouting system communicating with the construction simulation system, and a propelling system used for propelling the construction simulation system are included. Gravel soil is placed in the test box; the propelling system comprises a hydraulic jack and a counter-force frame fixedly connected with one end of the hydraulic jack; the counter-force frameis fixed on the bottom face; the construction simulation system comprises a first long pipeline 32 pre-embedded in the test box and a second short pipeline 31 connected with the first long pipeline 32in a sleeving manner; the data acquisition system comprises a static strain gauge, displacement detection sensors and miniature pressure sensors; and the displacement detection sensors and the miniature pressure sensors are connected with the static strain gauge. According to the method, conditions of any soft soil stratum, geometric scale of a tunnel, construction excavation process and synchronous grouting parameters are effectively simulated, and the flow and permeation of slurry are effectively observed.

The invention discloses a traffic state prediction method and device, and relates to the technical field of intelligent traffic. A specific embodiment of the method comprises the steps of determiningtraining sample data according to historical traffic data and first time period traffic data of a training road section and first time period traffic data of a road section adjacent to the training road section; wherein the historical traffic data is used as a first data source, the first time period traffic data of the training road section is used as a second data source, and the first time period traffic data of the road section adjacent to the training road section is used as a third data source; respectively determining the weight of each data source and the weight of each training sampleaccording to the training sample data; based on the training sample data, the weight of each data source, the weight of each training sample and a preset loss function, training to obtain a traffic model; and determining the traffic state of the to-be-predicted road section based on the traffic model. According to the embodiment, the influence of data disturbance can be effectively reduced, and the accuracy of traffic prediction is improved.

The present invention provides a method for synergistically suppressing combustion pressure pulsation by using a high-frequency excitation discharge center plasma and a side plasma, and relates to a method for suppressing pressure pulsation in a thermoacoustic oscillation phenomenon. In the present invention, synergy of a center plasma and a side plasma is taken as a dynamic and active way to regulate the pressure pulsation state of the combustion chamber during combustion. The method provided by the present invention is characterized in that plasmas are generated at the root and side of the flame in the combustion chamber, and the root plasma dynamically affects the frequency and the phase law of the flame heat release, so that the response degree of the pulsating flame to the airflow disturbance changes; the plasma applied on the side of the flame is input to the main body for absorbing the flame through certain energy to change the distance between the main flame heat release zone and the outlet of the combustion chamber, that is, the length of the return path reflected by the pressure pulsation in the combustion chamber from the outlet of the combustion chamber is changed, andthe phase difference between the pressure pulsation and the flame heat release rate changes; and at the same time, the synergy and adjustment of the plasmas at the two positions can achieve the slowing or suppression of the combustion pressure pulsation.

The invention discloses a probe for testing a lateral load of deep soil, which comprises a flat shovel probe. A micro rigid load bearing plate is arranged in the flat shovel probe; limitation of the micro rigid load bearing plate in the flat shovel probe is implemented by a steel ring; the micro rigid load bearing plate is connected with one end of a spring and the other end of the spring is connected with the flat shovel probe; a micro displacement sensor is fixedly arranged in the flat shovel probe; and the micro displacement sensor is used for continuously measuring the displacement of the micro rigid load bearing plate. The probe for testing the lateral load of the deep soil carries out field lateral load testing on the geotechnical engineering testing deep soil, can replace a conventional flat shovel lateral expansion test and is used for measuring a horizontal bearing force, a modulus of deformation, a static lateral pressure coefficient, a horizontal bedding coefficient and the like of the deep soil.

The invention provides a waste liquid pool aeration tube for sewage treatment, and a sewage treatment water purifying agent. The waste liquid pool aeration tube comprises an air inlet tube, a connecting cavity, aeration tubes and a tank body. A partial area in every aeration tube is designed to achieve synchronous rotation pushing, and the rotation direction is adjustable, so the aeration dispersity is greatly improved, and the stirring aeration effect on a waste liquid pool is improved by two times or above; and the structure of every aeration tube has a good promoting effect when used for releasing the water purifying agent, so the utilization rate of the water purifying agent is increased by 30%, and the comprehensive water treatment effect is remarkably improved.

The invention discloses an underground mould bag pile supporting method. The method includes the following steps that (1), pore-forming is conducted by using a drilling machine to form a mold bag hole, an injection pipe is arranged in the mold bag hole, a grouting outlet hole is formed in the injection pipe, the injection pipe is internally provided with a separator, a mold bag is arranged in themiddle rear section of the injection pipe, at least one grouting outlet hole formed in the injection pipe communicates with the mold bag, a draining pipe is arranged between the rear section of the mold bag and the outer wall of the injection pipe, and the front section of the injection pipe includes a segmented mold bag; (2), first grouting equipment is firstly used for injecting first grout intothe injection pipe to make the mold bag be saturated, then second grouting equipment is used for injecting second grout into the injection pipe, and the second grout flows out of the injection pipe from a front grouting outlet hole; and (3), grouting is conducted on the mold bag hole alternately, and grouting is conducted on a mold bag pile I firstly, and then grouting is conducted on a mold bagpile II after a mold bag I expands fully and achieves certain strength until a mold bag pile supporting wall structure is formed. The underground mould bag pile supporting method has the advantages ofbeing good in stress condition, capable of stopping water, capable of effectively controlling excavation subsidence and the like.

The invention discloses a tension type prestress anchor rod for fixing a soft rock stratum rock body and a construction method. The tension type prestress anchor rod comprises an anchor rod hole and aprestress rib, the part, located in the hole, of the prestress rib is divided into an inner anchoring section with an inner anchor and a free section from inside to outside, the anchor rod hole, where the inner anchoring section is located, of the prestress rib is an inversed conical hole large in top and small in bottom, and the part among the prestress rib, the inner anchor and the hole wall ofthe inversed conical hole is filled with a grouting material; the height of the inversed conical hole of the inner anchoring section is 350-500 mm; the height of the free section prestress rib is 1-4m; the hole diameter of the part, where the free section is located, of the prestress rib is 55-65 mm; a device capable of stretching in the inversed conical hole in the radial direction and thus locating an isolation connector is arranged on the isolation connector. The adhering and anchoring strength among the inner anchoring section prestress rib, the condensed grouting material and the hole wall is high, the tension type prestress anchor rod is simple in structure, the material is saved, the construction is convenient, the vibration to the rock body layer in the construction process is small, and the anchor rod is applicable to an environment preventing a rock body rock from generating a collapse geological disaster along the layer.

The invention discloses a layered mining method for an ultra-thick coal seam containing a dirt band layer in the middle, and belongs to the technical field of efficient mining of ultra-thick coal seams. The layered mining method comprises the four steps including layer dividing, first layer mining, second layer mining and bottom layer mining. During layer dividing, with the starting point of the high efficiency and the high recovery rate and the principle of reducing the mining disturbance influence, the layering positions and thicknesses are determined according to the broken-expansion coefficient of coal mass and the coal drawing height; a first layer is subjected to full-mechanized caving mining, and a metal net is laid at the bottom of a work face; a second layer is subjected to full-mechanized caving mining, and a goaf is filled maximally by utilizing the loose broken-expansion characteristics of the dirt band layer and the coal mass with a certain thickness on the upper part andthe lower part of the dirt band layer; and during bottom layer mining, all the coal mass subjected to broken-expansion is drawn at a time. According to the layered mining method, disturbance of layered mining of the ultra-thick coal seam on an overlying rock stratum can be reduced, middle dirt band and the coal mass near the dirt band are broken through two times of mining, thus drawing is easy, and the recovery rate can be increased effectively.

This invention relates to a self-pressurization type space low-infrared radiation cold-shield system device applied to an implementation of a space anti-infrared detection invisible aviation technology, which is an indispensable technology for space penetration attack under the condition of the modern high technology warfare. A low-temperature refrigerant carried by the system is pressurized by the method of self-pressurization during the space mid-course aviation process, and is throttled and refrigerated twice to implement the cold shield effect on a spacecraft, and to reduce intensity of infrared radiation of the surface of the system; or internal high temperature parts of the system in the air-operated friction course are cooled by a self-pressurization temperature control device during the starting and accelerating process to achieve the aim of space anti-infrared detection invisible aviation, and to enhance capability of space infrared visibility and penetration of the aircraft and finally to meet the demand on penetration of the space defence system of the opponent. The invention can reduce the intensity of the infrared radiation of the surface of the system and effectively improve the penetration capability of aircrafts by use of different refrigeration methods and different penetration technologies according to the demand on the practical air defence technology.