Abstract: This application provides a communication device, a base station, and a communication system. The communication device includes a power divider, a coupler group, and a multiplexer that are sequentially connected. The power divider is connected to the coupler group via at least two first paths. The power divider may divide a light beam into at least two split light beams, each split light beam is transmitted to the coupler group via one first path, and a phase difference and a time difference exist in transmission of any two split light beams in corresponding first paths.

Abstract: Provided is a system for engineering geomechanical experimental testing of a reservoir rock mass, including a stress control unit, a temperature control unit and a rock sample holder. The stress control unit includes a rigid pressure-applying mechanism and a flexible pressure-applying mechanism. The rigid pressure-applying mechanism is configured to apply rigid pressure to a rock mass via an indenter and a pressing piece. The flexible pressure-applying mechanism is configured to apply flexible pressure to the rock mass by using a pressure medium. Rigid pressure application and flexible pressure application are integrated to simulate a stress status under an actual geological condition better, and uniformity of pressure application is also ensured. The temperature control unit is configured to control a temperature of the rock mass via a heating mechanism and a cooling mechanism. A method for engineering geomechanical experimental testing of a reservoir rock mass is further provided.

Abstract: Disclosed are a visual optical system and a virtual reality device with the visual optical system. The visual optical system includes a first lens, a composite film layer, a second lens, and a partially reflective film in sequence from a first side to a second side along an optical axis; where each of the first lens and the second lens has a positive refractive power; the composite film layer is arranged on the second side surface of the first lens, the composite film layer includes a polarizing reflective film and a quarter-wave plate, and the polarizing reflective film is located between the first lens and the quarter-wave plate; and the partially reflective film is arranged on the second side surface of the second lens, and the second side surface of the second lens is a convex surface and also a Fresnel surface.

Abstract: A shear box for testing shear-seepage coupling characteristics of rock mass, and a method of using the shear box are provided, including an upper fixed shear box, and a lower movable shear box. A first extrusion block and an upper rock mass sample are arranged in a first placement groove of the upper fixed shear box. A second extrusion block and a lower rock mass sample are arranged in a second placement groove of the lower fixed shear box. A first elastic sealing member is arranged on each of both sides of the upper rock mass sample and the lower rock mass sample, and an elastic capsule is arranged on each of inner walls of both sides of the first placement groove and the second placement groove. An upper pressure head device for applying a force in a third direction is arranged on the upper fixed shear box.

Abstract: Provided is a sample fixture for an indirect tensile test of rock mass, relating to the technical field of rock mass engineering geomechanics tests. The sample fixture includes an upper fixture, and a lower fixture located below the upper fixture. The upper fixture includes an upper fixing block, a ball head, and an upper knife. The lower fixture includes a lower fixing block, a telescopic positioning plate, and a lower knife. The ball head is in fit with a spherical groove on an upper surface of the upper fixing block to achieve the function of transferring pressure, thus ensuring loading strength acting on a sample. A loading force is transferred by using a cutting edge of the upper knife to make the pressure act on the sample intensively, thus ensuring point or linear loading required by the test.

Abstract: A method and system for monitoring structural deterioration of a reservoir rock mass under a long-time high-temperature condition, and a product are provided. The method includes: arranging ultrasonic transducers and fiber optic extrinsic Fabry-Perot interferometric (EFPI) sensors in a loading briquette; loading ultrasonic waves on a rock mass sample with the ultrasonic transducers; monitoring ultrasonic and acoustic emission signals at the rock mass sample with the fiber optic EFPI sensors; inverting a velocity model indicating a change of a wave velocity inside the rock mass sample over time by fast marching acoustic emission tomography using standard optimization (FaATSO) according to the ultrasonic and acoustic emission signals; and conducting joint inversion by a fast-marching method according to the velocity model, the acoustic emission signals, and observation data to determine a position of rock mass fracturing in the rock mass sample.

Abstract: A sample mounting device for direct tensile test of rock mass is provided, which includes a first positioning stage, a second positioning stage, a first support piece, a second support piece, and a screw drive mechanism. The second positioning stage is arranged above the first positioning stage and capable of moving up and down, and cushion blocks for gluing with the rock mass are coaxially and detachably arranged at opposite ends of the first positioning stage and the second positioning stage, and a rock mass mounting area is formed between the two cushion blocks. A screw of the screw drive mechanism includes a first thread segment and a second thread segment with opposite thread directions. The first support piece is connected with the first thread segment through a nut seat, and the second support piece is connected with the second thread segment through a nut seat.

Abstract: A clamp and a shear test device are provided, and relate to the technical field of rock mass mechanics tests. The clamp comprises a box body, wherein an opening is formed in one side of the box body, two clamping structures are oppositely arranged in the box body, a sample is arranged between the two clamping structures, each clamping structure comprises an adjusting mechanism, and a distance between the two clamping structures is adjusted through adjusting mechanisms of the two clamping structures. According to the clamp, real-time dynamic adjustment is conveniently and rapidly achieved, the stability of sample clamping is ensured, and therefore the requirement that the shear load can be truly and effectively transmitted to the sample through the box body is met.

Abstract: An experimental system for simulating creep and stick-slip dislocations of a fault in a tunnel structure includes a box structure, a supporting device and a fault dislocation loading system. A friction effect layer, a first surrounding rock layer, a tunnel structure model, a second surrounding rock layer and an overburden pressure layer are sequentially arranged in the box structure from bottom to top. The bottom of the box structure is provided with a through hole. A plate assembly is provided on the through hole, and includes a first guide plate, a second guide plate and a loading plate. Inner sides of the first guide plate and the second guide plate are respectively provided with a first slide rail and a second slide rail. The loading plate moves along the first slide rail and the second slide rail under the action of the fault dislocation loading system.

Abstract: A variable angle loading testing machine is provided, which may include a bottom plate and a base fixedly connected to the bottom plate. A rock-sample accommodating cavity is formed in the base, and a rectangle-shaped sample is suitable for being placed into the rock-sample accommodating cavity. A side of the base is fixedly connected to two arc-shaped tension beams arranged in parallel, and a variable angle loading mechanism is slidably connected between the two arc-shaped tension beams. Through-holes are formed on the base, and an output end of the variable angle loading mechanism abuts against the rectangle-shaped sample through one of the through-holes. Loading and unloading of a stress with variable direction and magnitude under excavation disturbance can be simulated, which is of great significance for understanding mechanical behaviors of rock-soil mass under excavation disturbance.

Abstract: The present invention discloses a type of energy-absorbing rock bolt device with umbrella-shaped structure, which consists of a body of bolt, and one end of the said body of bolt is equipped with a preloaded system, as well as the other end of the said body of bolt is equipped with the first support system, in addition, the said body of bolt is equipped with several second support systems, and the said second support system is located between the said preloaded system and the said first support system; meanwhile, the said second support system consists of the first umbrella-shaped support system and the second umbrella support system.

Abstract: The present invention discloses a type of energy-absorbing rock bolt device with umbrella-shaped structure, which consists of a body of bolt, and one end of the said body of bolt is equipped with a preloaded system, as well as the other end of the said body of bolt is equipped with the first support system, in addition, the said body of bolt is equipped with several second support systems, and the said second support system is located between the said preloaded system and the said first support system; meanwhile, the said second support system consists of the first umbrella-shaped support system and the second umbrella support system.

Abstract: A rock mass shear test system for high-energy accelerator computed tomography (CT) scanning includes double horizontal loading devices, a first bearing device for bearing a static shear box, a second bearing device for bearing a dynamic shear box, and a normal loading device, etc. In the test, the double horizontal loading devices simultaneously apply an identical loading force to the rock mass, and the normal loading device applies a shear force to the rock mass. The double horizontal loading devices are provided in parallel and spaced apart, a loading force is applied in the horizontal direction, and a shear force is applied in the vertical direction, so that the loading cylinder and the rock mass sample are effectively prevented from interfering with each other during the accurate scanning process of the shearing progressive failure process of the rock mass.

Abstract: A test apparatus for simulating a seismic dynamic response of an underground cavern includes a loading frame, an overlying model and an underlying model of the underground cavern, a static loading device, a dynamic loading device and a measuring device. A vertical load and a horizontal load are separately applied by the static loading device to the overlying model to simulate real vertical and horizontal in-situ stresses of the in-situ underground cavern. A seismic dynamic load is applied by the dynamic loading device to the underlying model, and then acts on the overlying model to simulate a real seismic ground motion on the in-situ underground cavern. In this way, the present invention satisfies simulation requirements for the seismic dynamic response of the underground cavern to implement a high-fidelity simulation on the underground cavern through unified loading of the in-situ stress static load and the seismic dynamic load.

Abstract: A transportation device for an offshore platform, including a vessel and a floating structure which are fixedly connected. The floating structure is placed on a sea surface and is configured to assist the vessel to sail. The floating structure is provided with an adjustment mechanism which is configured to adjust the floating structure to rise and fall relative to the sea surface. A rail is arranged on the vessel and is in sliding connection with the topside module, so that the topside module slides onto the vessel from land. During the transportation of the topside module, the buoyancy of the floating structure is adjusted through the adjustment mechanism, so that the floating structure provides sufficient anti-rolling moments beside the vessel, thereby reducing the vibration of the topside module caused by the winds and waves during the sailing and reducing the potential damage to the topside module.

Abstract: A shear box for testing cyclic shear characteristics of a rock mass discontinuity includes: an upper shear box including an upper semi-open cavity composed of an upper left side plate, an upper right side plate, an upper front side plate, an upper rear side plate and an upper top plate; and a lower shear box including a lower semi-open cavity composed of a lower left side plate, a lower right side plate, a lower front side plate, a lower rear side plate and a lower bottom plate; the upper shear box includes at least one first adjusting device for adjusting a space size of the upper semi-open cavity; the lower shear box includes at least one second adjusting device for adjusting a space size of the lower semi-open cavity; and the upper shear box and the lower shear box are placed opposite to each other.

Abstract: A shear box for testing cyclic shear characteristics of a rock mass discontinuity includes: an upper shear box including an upper semi-open cavity composed of an upper left side plate, an upper right side plate, an upper front side plate, an upper rear side plate and an upper top plate; and a lower shear box including a lower semi-open cavity composed of a lower left side plate, a lower right side plate, a lower front side plate, a lower rear side plate and a lower bottom plate; the upper shear box includes at least one first adjusting device for adjusting a space size of the upper semi-open cavity; the lower shear box includes at least one second adjusting device for adjusting a space size of the lower semi-open cavity; and the upper shear box and the lower shear box are placed opposite to each other.

Abstract: The present invention relates to an offshore non-driven-in large-diameter monopile foundation structure and a construction method. An object of the invention is to provide an offshore non-driven-in large-diameter monopile foundation structure with simple structure, convenient construction and clear mechanic behavior, and a construction method. The technical solution adopted by the invention is as follows: an offshore non-driven-in large-diameter monopile foundation structure suitable for rock foundations is characterized in that a drilling hole is drilled in a rock foundation, a large-diameter monopile is implanted into the drilling hole, the bottom of the large-diameter monopile is sealed by underwater bottom-sealing concrete, and the gap between the outer wall of the large-diameter monopile and the hole wall of the drilling hole is filled with a grouting material goofed by a grouting system that is preset inside the large-diameter monopile.

Abstract: The present disclosure provides a method for transmitting a signal to multiple User Equipments (UEs) utilizing reciprocity of a wireless channel. In this method, a vector channel from the base station to each UE can be converted into an equivalent Single Input Single Output (SISO) channel having a strong Light-of-Sight (LOS) component using channel feedback. In this way, a reliable signal transmission to multiple UEs can be achieved with little channel training overhead. The present disclosure has prominent advantages such as simplicity in implementation, low processing complexity and very low channel training overhead and is particularly applicable in low-speed transmission of broadcast signaling in a massive MIMO system and scenarios where the base station is to page inactive UEs.

Abstract: The present disclosure provides a method for transmitting a signal to multiple User Equipments (UEs) utilizing reciprocity of a wireless channel. In this method, a vector channel from the base station to each UE can be converted into an equivalent Single Input Single Output (SISO) channel having a strong Light-of-Sight (LOS) component using channel feedback. In this way, a reliable signal transmission to multiple UEs can be achieved with little channel training overhead. The present disclosure has prominent advantages such as simplicity in implementation, low processing complexity and very low channel training overhead and is particularly applicable in low-speed transmission of broadcast signaling in a massive MIMO system and scenarios where the base station is to page inactive UEs.