Abstract: A high-pressure liquid delivery system under a high centrifugal acceleration condition on an arm-centrifuge, comprising a centrifuge main engine, a ground liquid source, a ground delivery conduit, a centrifuge bottom rotary joint, a centrifuge rotary arm delivery conduit, a rotary arm-basket pin roll, a basket rotary joint, a basket delivery conduit and a basket conduit outlet. According to the present disclosure, the basket rotary joint is introduced to adapt to the change of the basket-rotary arm angle before and after the arm-type basket centrifuge works, so that the demand for water, electricity, oil and gas transportation of the centrifuge is met. Therefore, the design for the conduit of the centrifuge-basket part is solidified, and compared with the traditional solution that a high-pressure hose is connected to the basket, the centrifugal acceleration load of the load can be increased to more than 500 g.

Abstract: A hypergravity experimental apparatus and method for natural gas hydrate exploitation by hydraulic fracturing are provided. A high-pressure vessel contains a hydrate reservoir model placed in a water bath environment connected to a water bath temperature control module. An effective stress control module applies stress control. A fracturing reinforcement exploitation module conducts fracturing, reinforcement, and exploitation experiments. A model multi-physical field monitoring module performs monitoring. A hydrate preparation module communicates with the high-pressure vessel. The high-pressure vessel, the effective stress control module, and the fracturing reinforcement exploitation module are all under hypergravity, and the hydrate preparation module and the water bath temperature control module are under normal gravity.

Abstract: Disclosed in the present disclosure is a fast evaluation method of site seismic liquefaction hazard based on artificial intelligence algorithm: establishing a historical seismic and site information database, the database including a demand input module, a web crawler module, a data processing module, and a database module connected in sequence; a neural network model performs prediction to acquire a post-earthquake site dominant frequency; and, on the basis of the post-earthquake site dominant frequency, acquiring a site earthquake damage degree and seismic performance parameters. The present disclosure solves the problem of fast evaluating post-earthquake site earthquake damage and site seismic performance parameters, and can rapidly evaluate the site liquefaction or softening earthquake damage degree and site seismic performance parameters in given earthquake conditions.

Abstract: The disclosure discloses a cone penetrometer for detecting multi-pollutants and the corresponding method based on laser induced fluorescence (LIF) and time domain reflectometry (TDR). The cone penetrometer includes two main modules: the TDR module mainly composes of a PEEK insulating rod, two gold-coated stainless steel probes and a coaxial cable; the LIF module mainly composes of endoscope image sensor, alumina glass lens, an ultraviolet LED with a 280 nm-wavelength, and an ultraviolet LED with a 325 nm-wavelength. Detection is performed to obtain the soil dielectric constant for characterizing the volumetric water content, electrical conductivity for the content of ionic pollutants, fluorescence intensity at 325 nm-wavelength for the content of polycyclic aromatic hydrocarbons, fluorescence intensity at 280 nm-wavelength for the content of humic acid, and soil images for soil types.

Abstract: Provided is a flexible thin film pressure sensor applicable in a hypergravity centrifugal environment, comprising a composite thin film, two metal electrodes, and a flexible composite encapsulation layer. The composite thin film includes a polyvinylidene fluoride (PVDF) matrix and a carbon nanowire filled within the PVDF matrix. The PVDF matrix includes a lower PVDF layer and an upper PVDF layer. The two metal electrodes are respectively fixed to two surfaces of the composite thin film and overlap with each other. A region of the composite thin film located between the two metal electrodes is a polarized region. The flexible composite encapsulation layer has a double-layer structure, wherein two layers of the double-layered flexible composite encapsulation layer are disposed on the two surfaces of the composite thin film, respectively, and edge portions of the flexible composite encapsulation layer extend beyond the composite thin film and are fixed to each other.

Abstract: Disclosed in the present disclosure is a fast evaluation method of site seismic liquefaction hazard based on artificial intelligence algorithm: establishing a historical seismic and site information database, the database including a demand input module, a web crawler module, a data processing module, and a database module connected in sequence; a neural network model performs prediction to acquire a post-earthquake site dominant frequency; and, on the basis of the post-earthquake site dominant frequency, acquiring a site earthquake damage degree and seismic performance parameters. The present disclosure solves the problem of fast evaluating post-earthquake site earthquake damage and site seismic performance parameters, and can rapidly evaluate the site liquefaction or softening earthquake damage degree and site seismic performance parameters in given earthquake conditions.

Abstract: The disclosure provides a device and a method for testing mechanical properties of a material under a high rotation speed and a high temperature. A sample chuck is installed on a main shaft of a centrifugal machine and rotates synchronously. A test sample is installed on the sample chuck. The induction heating system is installed on the centrifugal machine and does not rotate. The induction heating system is connected to a circulating water cooling system. A temperature controlling system is connected to the circulating water cooling system and the test sample. Parameters of the centrifugal machine, the test sample, etc. are determined. A temperature-controlling thermocouple and a strain gauge are installed on a standard section. A rotation speed of the centrifugal machine reaches the speed and is maintained until it breaks. Data is collected, and then the centrifugal machine is turned off and air-cooled to a room temperature.

Abstract: A vacuum chamber structure of an ultra-high gravity geotechnical centrifuge device, comprising: a cylindrical shell, a convex head, a bottom head, a lower bearing sealing cover, and a vacuum pressure-bearing chamber formed by sealing a top cylindrical cylinder and an upper sealing plate with sealing rings; wherein a high-speed rotor system is enclosed in the vacuum pressure-bearing chamber, and a cylindrical cooling device is installed between an internal side of the cylindrical shell and the high-speed rotor system. An annular cooling device is provided directly above the hanging baskets on both sides of the centrifuge arm. A vibration isolation expansion joint is arranged at the intersection of the high-speed rotor system and the cylindrical cylinder, which isolates the vibration of the main engine from the vacuum chamber and greatly reduces the vibration.

Abstract: An apparatus and a method for accurate flow control in a centrifugal supergravity environment. The apparatus comprises a control center, an oil supply module, a sensor module, an execution module and a centrifugal machine; the control center and the oil supply module are deployed in a normal gravity environment, and the sensor module and the execution module are deployed in a supergravity environment. According to the present application, the liquid level information of a model box, the piston position information of a servo actuator and the water supply flow information of the model box are collected by a sensor, and the information data are processed; control of the servo actuator is achieved by controlling an oil distributor; the flow fluctuation of a reciprocating water pump is weakened by the active complementation of flows of dual pump sets.

Abstract: An audio and video synchronization method and device (100) for a playback module, an electronic device (10) and a computer-readable storage medium are disclosed. The playback module includes an object-oriented program language standard library and an audio and video synchronization module of a kernel driver. The method includes: determining, in response to a playback instruction, a target player to build an audio module and a video module by the target player; creating, in the program language standard library, a synchronization instance corresponding to the target player, the synchronization instance having a unique instance identifier; and obtaining a reference clock corresponding to a real-time code stream of the synchronization instance based on the instance identifier, and controlling, according to a set synchronization mode, data outputs of the audio module and the video module corresponding to the target player based on the reference clock.

Abstract: A hypergravity model test device for simulating a progressive failure of a shield tunnel face, including a model box, a shield tunnel model, a servo loading control system and a data acquisition system. The servo loading control system includes a servo motor, a planetary roller screw electric cylinder and a loading rod. The data acquisition system includes a displacement transducer, an axial force meter, a pore pressure transducer, an earth pressure transducer and an industrial camera. The servo loading control system is connected to an excavation plate through the loading rod to control the excavation plate to move back and forth along an axial direction of the shield tunnel model at a set speed to simulate failure of the shield tunnel face. A method for simulating a progressive failure of a shield tunnel face is also provided.

Abstract: The disclosure discloses a cone penetrometer for detecting multi-pollutants and the corresponding method based on laser induced fluorescence (LIF) and time domain reflectometry (TDR). The cone penetrometer includes two main modules: the TDR module mainly composes of a PEEK insulating rod, two gold-coated stainless steel probes and a coaxial cable; the LIF module mainly composes of endoscope image sensor, alumina glass lens, an ultraviolet LED with a 280 nm-wavelength, and an ultraviolet LED with a 325 nm-wavelength. Detection is performed to obtain the soil dielectric constant for characterizing the volumetric water content, electrical conductivity for the content of ionic pollutants, fluorescence intensity at 325 nm-wavelength for the content of polycyclic aromatic hydrocarbons, fluorescence intensity at 280 nm-wavelength for the content of humic acid, and soil images for soil types.

Abstract: A device and a method for in situ penetration measurement of gas transport parameters in an unsaturated soil layer. The device mainly consists of a gas supply system, a gas concentration display recorder, a gas pressure display recorder, a sleeve, a gas concentration sensor, a gas pressure sensor, a porous gas-permeable tube and a conical penetration head. The gas diffusion coefficient and permeability coefficient of the unsaturated soil can be obtained by only measuring the gas pressure value, the gas concentration value and the corresponding gas flow value of an unsaturated soil layer at a depth required to be tested, and substituting same into calculation formulae of the gas diffusion coefficient and permeability coefficient. The testing process of the method is simple and fast, and is low in cost, simple in operation and convenient in calculation.

Abstract: A high-pressure liquid delivery system under a high centrifugal acceleration condition on an arm-centrifuge, comprising a centrifuge main engine, a ground liquid source, a ground delivery conduit, a centrifuge bottom rotary joint, a centrifuge rotary arm delivery conduit, a rotary arm-basket pin roll, a basket rotary joint, a basket delivery conduit and a basket conduit outlet. According to the present disclosure, the basket rotary joint is introduced to adapt to the change of the basket-rotary arm angle before and after the arm-type basket centrifuge works, so that the demand for water, electricity, oil and gas transportation of the centrifuge is met. Therefore, the design for the conduit of the centrifuge-basket part is solidified, and compared with the traditional solution that a high-pressure hose is connected to the basket, the centrifugal acceleration load of the load can be increased to more than 500 g.

Abstract: Provided is a supergravity directional solidification melting furnace equipment, including a supergravity test chamber and, mounted in the supergravity test chamber, a high-temperature heating subsystem, a crucible, and an air-cooling system. The supergravity test chamber is mounted with a wiring electrode and a cooling air valve device. The high-temperature heating subsystem is fixed in the supergravity test chamber. The crucible and the air cooling system are provided in the high-temperature heating subsystem. The high-temperature heating subsystem includes upper, middle, and lower furnaces, a mullite insulating layer, upper and lower heating cavity outer bodies, upper and lower heating furnace pipes, and a crucible support base. A high-temperature heating cavity is divided into upper and lower parts, is provided therein with a spiral groove, and is fitted with a heating element. The crucible support base is provided therein with a vent pipe channel into which a cooling air is introduced.

Abstract: A centrifugal testing device for simulating ground subsidence induced by buried pipeline leakage and infiltration includes a model box provided with a transparent observation window at a front side, a chamber partitioning plate, a damaged pipeline model, permeable plates, and a water-soil separation device. A front part of the model box is divided into a test soil chamber for filling model soil and seepage chambers located at two sides of the test soil chamber. A rear part of the model box is divided into a soil filtration chamber and water circulation supply chambers located at two sides of the soil filtration chamber. The damaged pipeline model includes a front end provided with an electric push rod for controlling a crack of the damaged pipeline model to be opened and closed and a rear end provided with a ball valve device and connected to a water pump.

Abstract: A centrifugal testing device for simulating ground subsidence induced by buried pipeline leakage and infiltration includes a model box provided with a transparent observation window at a front side, a chamber partitioning plate, a damaged pipeline model, permeable plates, and a water-soil separation device. A front part of the model box is divided into a test soil chamber for filling model soil and seepage chambers located at two sides of the test soil chamber. A rear part of the model box is divided into a soil filtration chamber and water circulation supply chambers located at two sides of the soil filtration chamber. The damaged pipeline model includes a front end provided with an electric push rod for controlling a crack of the damaged pipeline model to be opened and closed and a rear end provided with a ball valve device and connected to a water pump.

Abstract: An apparatus and a method for accurate flow control in a centrifugal supergravity environment. The apparatus comprises a control center, an oil supply module, a sensor module, an execution module and a centrifugal machine; the control center and the oil supply module are deployed in a normal gravity environment, and the sensor module and the execution module are deployed in a supergravity environment. According to the present application, the liquid level information of a model box, the piston position information of a servo actuator and the water supply flow information of the model box are collected by a sensor, and the information data are processed; control of the servo actuator is achieved by controlling an oil distributor; the flow fluctuation of a reciprocating water pump is weakened by the active complementation of flows of dual pump sets.

Abstract: A vacuum chamber structure of an ultra-high gravity geotechnical centrifuge device, comprising: a cylindrical shell, a convex head, a bottom head, a lower bearing sealing cover, and a vacuum pressure-bearing chamber formed by sealing a top cylindrical cylinder and an upper sealing plate with sealing rings; wherein a high-speed rotor system is enclosed in the vacuum pressure-bearing chamber, and a cylindrical cooling device is installed between an internal side of the cylindrical shell and the high-speed rotor system. An annular cooling device is provided directly above the hanging baskets on both sides of the centrifuge arm. A vibration isolation expansion joint is arranged at the intersection of the high-speed rotor system and the cylindrical cylinder, which isolates the vibration of the main engine from the vacuum chamber and greatly reduces the vibration.

Abstract: Provided is a material performance testing system under a fixed multi-field coupling effect in a hypergravity environment, including a hoisted sealed cabin, a bearing frame, a high-temperature furnace, a mechanical test device, and a buffer device. The bearing frame and the high-temperature furnace are fixedly mounted inside the hoisted sealed cabin. The bearing frame is covered on the high-temperature furnace. The buffer device is mounted at a bottom of the high-temperature furnace. Upper and lower ends of the mechanical test device are connected in a top of the bearing frame and the bottom of the high-temperature furnace. A sample is connected and mounted at an end of the mechanical test device.