Abstract: Disclosed are a system and method for online detection of a junction temperature of a semiconductor device, and a controller. The system includes a controller, an online measurement circuit, and a detection module configured to extract saturated drain current information of a device under test; one end of the online measurement circuit is connected to a drain of the device under test; the other end of the online measurement circuit is connected to a source of the device under test; when the device under test enters a saturation region to operate, an energy storage element in the online measurement circuit spontaneously injects current into the drain of the device under test, so that the drain current of the device under test rises; the controller determines the junction temperature of the device under test according to the saturated drain current information of the device under test extracted by the detection module.

Abstract: An ultrahigh-speed bar precision shearing device adopting a type of alternating current servo motors driving a flywheel to spirally compress nitrogen for energy storage includes a frame structure, a high-pressure air chamber mechanism, a hammer head movement mechanism and a mold are installed on the frame structure from top to bottom, the high-pressure air chamber mechanism cooperates with the hammer head movement mechanism to strike the mold, and bars are cut off and separated under the effect of the mold. The present application omits a complex hydraulic driving system, and ultrahigh-speed striking (20-30 m/s) of a hammer head is achieved in a manner of a flywheel spirally compressing nitrogen for energy storage; and control is simple, the return speed of the hammer head is high, and the energy utilization rate is high.

Abstract: An in-situ evaluation method and system for loess collapsibility based on non-destructive time-domain reflection technology, includes: calculating loess dry density and mass water content; considering loess dry density, mass water content and basic physical property indicators, and evaluating loess collapsibility in situ through mathematical models. The loess collapsibility in-situ evaluation method based on the non-destructive time domain reflectometry technology of the present invention can not only realize whether the loess has collapsibility, but also has the potential to distinguish strong, medium and slight collapsibility.

Abstract: The present invention relates to the technical field of magnetron sputtering process, and specifically to a method for improving the uniformity of rare earth nickelate thin film deposited by reactive magnetron sputtering, comprising the following steps: adjusting the sputter angle of a Ni target toward a substrate to perform magnetron sputtering to deposit a thin film, and obtaining the content data of the Ni element in the deposited thin film; analyzing the content data of the Ni element to screen out the sputter angle for realizing zero-gradient deposition of the Ni element on the substrate surface; similarly, screening out the sputter angle for realizing zero-gradient deposition of the RE element on the substrate surface; preparing a nickelate thin film according to the screened zero-gradient sputter angle of Ni target material and the RE target material so as to improve the deposition uniformity of the rare earth nickelate thin film.

Abstract: The present invention discloses a multi-header pipe distributing annular printed circuit heat exchanger, and pertains to the technical field of heat exchangers, the heat exchanger includes: a front head configured to achieve same side entry and exit of a cold fluid; a core body with one end thereof connected with the front head and configured to achieve distributing of cold fluid entry and exit; a hot fluid inlet cavity provided in a middle portion of the core body and configured to achieve entry of a hot fluid; a shell sheathed outside the core body, and the shell and the core body provided with a gap for collecting the hot fluid; and a lower cover plate connected with one end of the core body and configured to block the hot fluid inlet cavity. The present invention can improve compactness and power density of the heat exchanger, reduce volume and weight.

Abstract: A method for preparing fluorescent carbon quantum dots by using gas-liquid two-phase plasma is provided, which relates to the field of fluorescent carbon quantum technology. On the basis of liquid phase plasma, an inert gas is introduced to generate plasma by a gas-liquid two-phase discharge method. The introduction of inert gas facilitates the formation of discharge channels, reduces the difficulty of product synthesis, improves mass transfer rates of active particles, helps to improve synthesis rates of carbon nano-products, increases discharge contact area and enhances discharge stability. A high reaction efficiency and a short time consumption can be realized. A pulsed power supply is adopted for discharge, which has lower energy consumption compared with the direct current discharge. Moreover, the process is simple, raw materials are easy to obtain, and there is no need for catalysts, strong oxidants or strong corrosives, so the purity of the product maybe higher.

Abstract: The present disclosure relates to a method for obtaining lead-free piezoelectric materials, including: Step S100, adjusting the T/O phase boundary of a first lead-free piezoelectric material: for the first lead-free piezoelectric material, adjusting the T/O phase boundary between the tetragonal phase T and the orthorhombic phase O to be near the room temperature by doping; Step S200, further adjusting the C/T phase boundary and the O/R phase boundary: further adjusting the C/T phase boundary between the cubic paraelectric phase C and the tetragonal phase T, and the O/R phase boundary between the orthorhombic phase O and the rhombohedral phase R by doping, so as to enable the C/T phase boundary and the O/R phase boundary to approach the T/O phase boundary; and Step S300, obtaining second lead-free piezoelectric materials: obtaining multiple second lead-free piezoelectric materials with different piezoelectric constants d33 and different Curie temperatures TC in the process.

Abstract: A cyber-physical integrated restoration method and system for distribution systems based on emergency mobile communications are provided. After extreme natural disasters which cause serious damage to distribution systems, damages of distribution systems are evaluated through system feedback data. When ground communication base stations are unavailable due to the damages, the method can make full use of existing wireless emergency communication resources to provide emergency communication services, and quickly restore the power supply through distribution automation functions with supports of the backup battery of automatic terminal devices, so as to effectively improve the resilience of distribution systems.

Abstract: An alginate hydrogel-based thin-film heat flux sensor for billet crystallizer includes an alginate hydrogel substrate. The alginate hydrogel substrate is configured in a U-shaped planar structure. The U-shaped planar structure includes a first side and a second side, and the first side is longer than the second side. An inner surface of the alginate hydrogel substrate is provided with a first film thermocouple and a second film thermocouple. The first film thermocouple is in crosslinking connection with the second film thermocouple.

Abstract: The present disclosure provides a data processing method, a device, a computer apparatus and a storage medium, wherein the method includes: in response to a target disk receiving at least one write request within a preset time period, determining a size threshold value for classifying a data update type according to a size of write data respectively indicated by each write request; determining a data update type corresponding to each write request according to a size of each write request and the size threshold value; dividing write data of the write request to obtain a data block according to a preset data block size, and caching the data block in a cache region of the target disk corresponding to the data update type, the target disk has multiple types of cache regions configured therein, different cache regions are configured to support caching of data with different update frequencies.

Abstract: A plasma-activated gas disinfection device includes a plasma generating unit, a disinfection chamber, an air pump and a fluid control module, where the plasma generating unit works in a first working mode during a first time period, and generates a first plasma active gas in the first working mode; the plasma generating unit works in a second working mode during a second time period, and generates a second plasma active gas in the second working mode; and the first time period is before the second time period, and alternatively, the first time period is after the second time period, such that a disinfection object in the disinfection chamber is disinfected. The plasma generating unit in the present disclosure is a simple device, and only one discharge module is used for generating different plasma active gases.

Abstract: A method of preparing biodegradable Zn—Mg—Bi zinc alloy includes: melting magnesium under an inert atmosphere to obtain a magnesium melt; adding bismuth particles to the magnesium melt followed by reaction under stirring and heat preservation treatment to obtain a Mg—Bi alloy melt; allowing the Mg—Bi alloy melt to stand in a furnace; subjecting the Mg—Bi alloy melt to refining, slagging-off, casting and demoulding to obtain Mg-50 wt. % Bi alloy ingot; melting zinc to obtain a zinc melt; adding the Mg-50 wt. % Bi alloy ingot and pure magnesium or pure bismuth followed by heating to a preset temperature, stirring and heat preservation to obtain a Zn—Mg—Bi alloy melt; allowing the Zn—Mg—Bi alloy melt to stand in a furnace followed by refining, slagging-off, casting and demoulding to obtain the biodegradable Zn—Mg—Bi zinc alloy.

Abstract: The present disclosure provides a data processing method, a device, a computer apparatus and a storage medium, wherein the method includes: in response to a target disk receiving at least one write request within a preset time period, determining a size threshold value for classifying a data update type according to a size of write data respectively indicated by each write request; determining a data update type corresponding to each write request according to a size of each write request and the size threshold value; dividing write data of the write request to obtain a data block according to a preset data block size, and caching the data block in a cache region of the target disk corresponding to the data update type, the target disk has multiple types of cache regions configured therein, different cache regions are configured to support caching of data with different update frequencies.

Abstract: A method for evaluating the mechanical state of a high-voltage shunt reactor based on vibration characteristics is disclosed, relating to the technical field of electrical equipment fault diagnosis. The method includes: based on historical state data and real-time vibration and noise signal data of the high-voltage shunt reactor and through an LSTM neural network time series prediction method, comparing deviation between predicted characteristic value and actual characteristic value, and determining whether the high-voltage shunt reactor has mechanical defects or failures. By using the historical state data and the real-time vibration and noise signal data of the high-voltage shunt reactor, an LSTM neural network time series prediction method, as well as comparison of the deviation between the predicted characteristic value and the actual characteristic value, etc., the evaluation of the mechanical state of the high-voltage shunt reactor is realized.

Abstract: The present disclosure relates to the field of strain sensors, and specifically relates to a high-temperature thin-film strain sensor, including a substrate and a strain-sensitive grid. The strain-sensitive grid includes an indium tin oxide layer and a platinum layer, the indium tin oxide layer is deposited on the substrate, and the platinum layer is deposited on the indium tin oxide layer. The indium tin oxide layer contains 50% by mass of indium oxide and 50% by mass of tin oxide. The high-temperature thin-film strain sensor provided by the present disclosure can be used in an environment from room temperature to 500° C., and have extremely high sensitivity at a high temperature of 500° C. Unlike the conventional metal foil strain gauge with a thickness of several microns, the high-temperature thin-film strain grid has a thickness of 500 nm, which can better convey the strain of the measured object at high temperature.

Abstract: A power-assisted negative pressure type flexible exoskeleton system used for an extravehicular spacesuit. The system includes an exoskeleton pneumatic control system, a plurality of inertial sensors, a plurality of negative pressure type flexible actuators and a plurality of flexible bending sensors, wherein pneumatic energy is provided for the exoskeleton system by a gas source in the exoskeleton control system, compressed air is cleaned by a water-separating gas filter, normal work of a pneumatic actuating element is guaranteed, a pressure reducing valve and a pressure gauge carry out voltage stability control on the output pressure of the gas source, a two-position two-way valve serves as a gas source switch valve, and three-position three-way valves, proportional pressure valves and the flexible actuators form four pneumatic control loops of the left and right elbow joints and the left and right knee joints of the exoskeleton system.

Abstract: A gas-fired steam boiler, including multiple heat exchange tubes, an upper steam header, a lower steam header, a casing, a burner, a condenser, a chimney, and a controller. The heat exchange tubes are vertically arranged to form an annular tube row. A space enclosed by the annular tube row is configured as a furnace. Adjacent two heat exchange tubes are combined to form a gap channel evenly distributed along a circumferential direction. A width of the gap channel is 0.1-4 mm, and a circumferential length of the gap channel is 50-300 mm. A length of the gap channel along an axial direction of the heat exchange tube is the same as a length of the heat exchange tube.

Abstract: The present disclosure provides a wireless sensor, a manufacturing method thereof and a wound flatness detection system. The wireless sensor includes a sensing element, two elastomer-made encapsulation layers and a breathable fiber-made encapsulation layer; wherein the sensing element is manufactured by the following steps: step 1: preparing a thin film using a carbon-based polymer solution; step 2: using a low-energy laser to induce molecular reconstruction of carbon-based groups on surfaces of the thin film to form a resistance-sensitive layer; step 3: using a high-energy laser to modify, carbonize and cut the resistance-sensitive layer to form a patterned sensing element. The present disclosure solves the problems that existing pressure or tension sensors are extremely susceptible to static interference from the external environment and the human body, and the mechanical mismatch between the sensing layer and the substrate, as well as the impermeability problem.

Abstract: A method for analyzing debris bed formation based on a multi-resolution multiphase particle algorithm, which uses the least-squares moving particle semi-implicit method with second-order computational accuracy and improves surface tension model and free surface particle identification model. The method also utilizes a particle-based gas-liquid phase transition model and a particle-based liquid-solid phase transition model with multi-resolution features, such that the coolant vaporization and melt solidification processes during the falling process of the melt can be calculated. Moreover, a solid-solid collision model is coupled to calculate the collision and debris bed deformation during the falling process of the debris particles. In this way, the momentum exchange, energy transfer and phase transition between different phases are taken into account, and the computational instability caused by the large physical difference between phases is mitigated.

Abstract: A customized method for strengthening the water droplet erosion (WDE) resistance on steam turbine blade surfaces having the following steps: step S1: carrying out numerical analysis about erosion characteristics on blade surfaces to predict water erosion prone areas; Step S2: designing corresponding structures against WDE, and conducting a test for WDE characteristics of structures to screen effective structures; Step S3: according to the areas detected in Step S1, selecting a suitable and effective structure from the test and determining where and how to arrange the structure on the blade surface is disclosed. The above-mentioned method can detect areas prone to blade erosion by numerical simulation, and arrange the structures screened out by test of WDE characteristics to improve the WDE resistance of blades, mitigating the WDE problem so only a small number of special structures in local areas are arranged, thereby minimizing cost and influence on steam turbine blades.