A simulation test method for gas extraction from a tectonically-deformed coal seam in-situ by depressurizing a horizontal well cavity. A coal series stratum structure reconstruction and similar material simulation subsystem simulates a tectonically-deformed coal reservoir. A horizontal well drilling and reaming simulation subsystem constructs a U-shaped well in which a horizontal well adjoins a vertical well, and performs a reaming process on a horizontal section thereof. A horizontal well hole-collapse cavity-construction depressurization excitation simulation subsystem performs pressure-pulse excitation and stress release on the horizontal well, and hydraulically displaces a coal-liquid-gas mixture such that the mixture is conveyed towards a vertical well section. A product lifting simulation subsystem further pulverizes the coal and lifts the mixture. A gas-liquid-solid separation simulation subsystem separates the coal, liquid and gas. A monitoring and control subsystem detects and controls the operation and the execution processes of equipment in real time.

A method for determining characteristics of a crack detected in a material, comprising: determining initial mechanical loads applied to the material, applying a plurality of crack-opening mechanical loads to the material, each opening mechanical load being a linear combination of the initial mechanical loads, and measuring the relative displacement of the first point with respect to the second point induced by each opening mechanical load, applying a plurality of crack-closing mechanical loads to the material, each closing mechanical load being a linear combination of the initial mechanical loads, and measuring the relative displacement of the first point with respect to the second point induced by each closing mechanical load, and estimating the direction of the crack as a function of the amplitude of each opening and closing mechanical load applied to the material and of the measured relative displacements.

In a case where control input is performed via a low-pass filter, a control gain more appropriate for both stability and responsiveness is set according to setting of the low-pass filter. A control unit (21) performs control input for a load mechanism (40) via a low-pass filter, discriminates a stability of a control system including the load mechanism (40) and the low-pass filter when setting of the low-pass filter is changed, sets an appropriate control gain based on a maximum control gain at which an excess amount of a measured value with respect to a target value is equal to or less than a predetermined value within a range where that the control system is stable, and controls an operation of the load mechanism (40) by using the appropriate control gain.

A hardness tester includes a measurer (CPU) measuring a value for a material characteristic of a sample in conjunction with formation of an indentation, an acquirer (CPU) acquiring measurement data associated with the value for the material characteristic of the sample measured by the measurer, and a determiner (CPU) accumulating a predetermined value for the material characteristic based on the measurement data acquired by the acquirer and determining a time to replace the indenter based on the accumulated value for the material characteristic.

A vacuum system and method for inspecting a workpiece that can include use of the vacuum system, where the vacuum system can include a housing defining at least a portion of a vacuum chamber, a piston within the housing that oscillates to vary a volume of the vacuum chamber, a first valve and a second valve in fluid communication with the vacuum chamber, and a hood in fluid communication with the second valve and the vacuum chamber. The vacuum system can include high-speed valves that enable vacuum system cycling and thus vacuum pressure cycling at a rapid frequency.

An apparatus and a method for in-situ testing impact strength of a micro-structure are provided. In one embodiment, the apparatus includes: a flexible beam, one end of which being fixed; an impact mass block disposed at the other end of the flexible beam and being for exerting an impact on the micro-structure; and a locking member including a beam arm and a plurality of locking teeth. The beam arm is perpendicular to the flexible beam and one end of the beam arm is fixed, and the plurality of locking teeth are distributed at intervals along the beam arm, such that the other end of the flexible beam is engaged to one of the plurality of locking teeth when the flexible beam is loaded.

A vacuum system and method for inspecting a workpiece that can include use of the vacuum system, where the vacuum system can include a housing defining at least a portion of a vacuum chamber, a piston within the housing that oscillates to vary a volume of the vacuum chamber, a first valve and a second valve in fluid communication with the vacuum chamber, and a hood in fluid communication with the second valve and the vacuum chamber. The vacuum system can include high-speed valves that enable vacuum system cycling and thus vacuum pressure cycling at a rapid frequency.

An actuator control system, mechanical testing system, and method for adaptive control of an actuator of a mechanical testing device may include determining a stiffness of a medium that the actuator is moving through and/or load gain of the actuator, wherein the stiffness and load gain is determined by generating a waveform to actuate the actuator until a load sensor signal and/or a displacement sensor signal is received, and controllably moving the actuator through the medium according to a predefined constant velocity by calculating a current request using the stiffness of the medium, and/or adjusting the load of the actuator in accordance with a constant load ramp rate.

An actuator control system, mechanical testing system, and method for adaptive control of an actuator of a mechanical testing device is provided. The method may include applying a mechanical load to the specimen with the actuator, resulting in receiving a load sensor signal from a load sensor and a displacement sensor signal from a displacement sensor, determining a plurality of dynamic characteristics of the mechanical testing device throughout a length of the test from data received from the load sensor signal and the displacement sensor signal, and controlling the actuator based on the plurality of dynamic characteristics to adapt the actuator to track a desired performance of the actuator.

A water hydraulic test on test pipes having a wide range of sizes is conducted accurately, efficiently, and economically, by using a plurality of booster cylinders arranged in parallel with respect to a test pipe and having respective boosting ratios increasing in stages. A plurality of servo motor driven pumps arranged in parallel is used as a drive source for the plurality of booster cylinders. Before a water pressure on an output side of the booster cylinder reaches a pressure near a test pressure, the plurality of servo motor driven pumps operates simultaneously. Then, the plurality of servo motor driven pumps stops operating except one and the water pressure on the output side of the booster cylinder is increased to the test pressure by the one servo motor driven pump. During pressure increase, the plurality of booster cylinders is used in turn in order of increasing boosting ratio.