Abstract: A dynamic simulation test platform for ultra-high-speed evacuated tube magnetic levitation (maglev) transportation includes an evacuated tube having a transition section and a vacuum section, a vacuum maintaining system, a motor supporting platform, and a model train. One end of the evacuated tube is provided with a first isolation door, and the other end is closed. A second isolation door is provided inside the evacuated tube. The vacuum maintaining system is connected to the transition section and the vacuum section. The motor supporting platform is provided in the evacuated tube and extends outside the transition section. The motor supporting platform is provided with a stator winding and a permanent-magnet track. A mover and a cryogenic dewar are provided at a bottom of the model train. The cryogenic dewar is provided with a superconducting bulk. A test method using the test platform is further provided.

Abstract: An automatic transport device for cleaning machines includes a transport base. A lifting-lowering assembly and a tray are provided on the transport base. The tray is connected to the transport base through the lifting-lowering assembly, and can be driven by the lifting-lowering assembly to reciprocate in a height direction. A top surface of the tray is provided with a translation assembly for transferring the shelf to the transport platform. A first mounting cavity is provided at each of front and rear ends of the tray. The translation assembly is connected to a side wall of the first mounting cavity. A second mounting cavity is provided at each of right and left ends of the tray. The second mounting cavity is provided with a limiting assembly, a lifting-lowering sensing assembly and a distance sensing assembly. An interactive system is provided in the transport base.

Abstract: A high-speed train derailment arresting system is provided, which includes multiple passive protection arresting devices arranged on both sides of a high-speed railway line. The passive protection arresting device includes a rigid support assembly fixed on a respective side of the high-speed railway line and a rotating protective barrel arranged on the support assembly. A structural design method for the high-speed train derailment arresting system is further provided.

Abstract: Disclosed is a method fir measuring a deviation angle of a fatigue microcrack based on nonlinear ultrasound, comprising: preliminarily positioning a fatigue microcrack to obtain a center of the microcrack; selecting a horizontal positive direction, and defining an orientation angle; drawing a positive circumference on a surface of a metal plate, and selecting a fixed interval angle; placing an excitation sensor and a receiving sensor on the drawn positive circumference according to the orientation angle; ultrasonically testing each group of ultrasonic sensing paths, and recording time domain waveform signals formed by each group of ultrasonic sensing paths; converting each group of time domain waveform signals into a corresponding frequency domain graph, extracting an ultrasonic fundamental wave signal amplitude and a second harmonic waveform amplitude, and calculating a relative nonlinear coefficient; drawing an orientation angle-relative nonlinear coefficient polar coordinate graph; and determining a deviat

Abstract: There is provided a method of receiving a transmitted signal over a time-varying channel. The method includes: obtaining a received symbol signal in frequency domain based on the transmitted signal; performing a first channel estimation based on the received symbol signal to obtain a plurality of first estimated BEM coefficients; performing a first equalization based on the received symbol signal and the plurality of first estimated BEM coefficients to obtain a plurality of first detected source symbols; and performing one or more rounds of a second channel estimation and a second equalization.

Abstract: An angular domain channel estimation method based on matrix reconstruction for a symmetrical nonuniform array is a combined two-stage channel estimation and channel equalization scheme provided based on an SNLA model. In a first stage, a matrix reconstruction method is used to estimate a path AOA, and compared with traditional channel estimation based on ULA, the matrix reconstruction method achieves a higher resolution ratio. In a second stage, an LS method is used to obtain a path gain. According to the angular domain channel estimation method, a mean square error of channel estimation, a bit error of data transmission and complexity of a traditional scheme are significantly reduced. A simulation result indicates that compared with the traditional method, the angular domain channel estimation method can achieve a lower MSE and BER.

Abstract: An angular domain channel estimation method based on matrix reconstruction for a symmetrical nonuniform array is a combined two-stage channel estimation and channel equalization scheme provided based on an SNLA model. In a first stage, a matrix reconstruction method is used to estimate a path AOA, and compared with traditional channel estimation based on ULA, the matrix reconstruction method achieves a higher resolution ratio. In a second stage, an LS method is used to obtain a path gain. According to the angular domain channel estimation method, a mean square error of channel estimation, a bit error of data transmission and complexity of a traditional scheme are significantly reduced. A simulation result indicates that compared with the traditional method, the angular domain channel estimation method can achieve a lower MSE and BER.

Abstract: The present invention provides a three-phase power supply and collection device for a maglev train. A cross beam is arranged at the middle part of the bogie of the maglev train, and the lower surface of the cross beam is provided with three sets of longitudinal bearing seats, and three insulating bushes, three collector shoes and three power supply rails corresponding to the longitudinal bearing seats; the two ends of the horizontal part of each insulating bush is a rotating shaft structure, and the vertical part of the insulating bush is a hollow tubular structure; the upper part of each collector shoe is the shoe handle, the lower part is the shoe body, and the bottom of the shoe body is in a concave semicircular shape; the top surface of each power supply rail is in a convex semicircular shape.

Abstract: A super-compact arrayed waveguide grating (AWG) wavelength division multiplexer based on a sub-wavelength grating is provided and includes an input waveguide, a first planar waveguide, an arrayed waveguide, a second planar waveguide, and the output waveguide that are sequentially connected. The input waveguide has 1 port, and the output waveguide has 8 ports. The arrayed waveguide includes 50 equivalent uniform strip waveguides with the same length difference, and each of the equivalent uniform strip waveguides is configured as a sub-wavelength grating structure, thereby forming the effect of increasing group refractive index or transmission delay based on a slow light effect. The 8 channels with a channel spacing of 200 GHz have the minimum adjacent channel crosstalk of less than ?27 dB, and the overall size is within 300×230 ?m2. In the multiplexer, the overall integration size of the device is reduced by an order of magnitude.

Abstract: A detachable cryostat includes many novel structures. Two radiation shields are installed in the detachable cryostat. One of the radiation shields is cooled by the second-stage cold chamber utilized to contain a cryogen, and the other one is cooled by the first-stage cold head of the cryocooler. These structures are both used for reducing heat loads from an outside. The resilient supporting device, the resilient circular sleeve, the bellows and the conductive blocks are utilized to achieve excellent thermal contact and complete thermal isolation between the cryocooler and the cryogen. A detachable binary current lead device can be introduced in the detachable cryostat, wherein, the detachable binary current lead includes a superconducting current lead and a copper current lead. When the installation adjustment mechanism is tightly pressed and loosened, it can enable the superconducting current lead to contact and separate from the copper current lead.

Abstract: Provided herein are a lappaconitine derivative of formula (I), and a preparation and application thereof.

Abstract: A levitation, propulsion and guidance integrated magnetic levitation system and an improvement method of levitation and guidance. The system includes a maglev train and a maglev track. The maglev train is provided with a permanent magnet array. The maglev track is provided with a driving device and a levitation driving device in sequence along a running direction of the maglev train. An iron plate is arranged in the middle of the maglev track. The driving device accelerates the maglev train from 0 to take-off velocity. The levitation driving device provides a driving force and a levitation force for the maglev train. The iron plate enables the centered running of the maglev train.

Abstract: A train driver assistance method includes: acquiring basic data of a train under a complex and severe condition; determining whether a traction power system is normal according to the basic data; if so, acquiring an energy-efficient optimized speed profile of the train in a normal state according to the basic data of the train in the current state; and if not, acquiring an energy-efficient optimized speed profile of the train in an abnormal state according to the basic data of the train in the current state. In this way, the method can acquire the energy-efficient optimized speed profile of the train in its current state. The comprehensive electric train driver assistance method can enable the train to adapt to the complex and severe environment and realize the energy-efficient operation of the train and self-rescue of the train.

Abstract: An adaptive method of cleaning structural health monitoring (SHM) data based on local outlier factor is provided, including following steps: step 1: dividing SHM data to be analyzed into a series of data segments by using adaptive sliding window (ASW) technology; step 2: extracting time-domain statistical factors and frequency-domain statistical factors of each of the data segments to refine data information, thereby forming objects for study; step 3: calculating an outlier degree of each of the objects by using a weighted multiscale local outlier factor (WMLOF) based on feature factors; and step 4: detecting anomalies in SHM data by comparing a WMLOF value with a threshold value. The adaptive method can improve data quality effectively.

Abstract: A permanent magnet electrodynamic suspension system includes a conductor track and a suspension and guidance device. The conductor track is disposed on a roadbed, and the suspension and guidance device is disposed above the conductor track. The suspension and guidance device includes a first permanent magnet array and a second permanent magnet array. The first permanent magnet array and the second permanent magnet array are the same in the magnetization direction arrangement. The first permanent magnet array and the second permanent magnet array are arranged perpendicular to each other. A guidance method for the permanent magnet electrodynamic suspension system is further provided.

Abstract: A chlorin compound, and a preparation and use thereof, related to medicine. The chlorin compound is represented by formula (I), or a salt, a stereisomer, a hydrate, a solvate or a prodrug thereof.

Abstract: An integrated photonics millimeter wave (MMW) radar communication system based on analog phase modulation scheme includes an integrated photonics MMW radar communication signal transmitter, a radar receiver, and a communication receiver. The transmitter includes a radar communication signal analog phase modulation module, an optical frequency comb (OFC) module, an electro-optic modulator (EOM), an optical shaping filter, an optical power divider, a photoelectric detector, an electric power amplifier, and a transmitting antenna that are cascaded sequentially. The radar receiver includes a radar receiving antenna, an electric low-noise amplifier (LNA), an optical phase modulator, an optical bandpass filter (BPF), a low-speed photoelectric detector, an electric low-pass filter, and a low-speed oscilloscope that are cascaded sequentially.

Abstract: A ballastless track roadbed damage forewarning method considering uncertainty includes the following steps. Step 1: counting roadbed material parameters and precipitation; Step 2: establishing a FLAC-PFC model of a ballastless track roadbed and calibrating mesoscopic parameters of a roadbed surface layer; Step 3: generating a lognormal random field of particle contact friction coefficients and assigning it to particle contact nodes of the roadbed surface layer; Step 4: perform sampling on the precipitation and adjusting a fluid domain of the roadbed surface layer; Step 5: determining a worst spatial correlation distance in the random field; and Step 6: calculating a damage probability pf of the roadbed surface layer under the worst spatial correlation distance; outputting alarm information when pf exceeds an alarm threshold, otherwise, quitting. The method monitors and gives early warning of damage to the roadbed surface layer under dynamic loads, ensuring driving safety.

Abstract: A super-compact arrayed waveguide grating (AWG) wavelength division multiplexer based on a sub-wavelength grating is provided and includes an input waveguide, a first planar waveguide, an arrayed waveguide, a second planar waveguide, and the output waveguide that are sequentially connected. The input waveguide has 1 port, and the output waveguide has 8 ports. The arrayed waveguide includes 50 equivalent uniform strip waveguides with the same length difference, and each of the equivalent uniform strip waveguides is configured as a sub-wavelength grating structure, thereby forming the effect of increasing group refractive index or transmission delay based on a slow light effect. The 8 channels with a channel spacing of 200 GHz have the minimum adjacent channel crosstalk of less than -27 dB, and the overall size is within 300×230 µm2. In the multiplexer, the overall integration size of the device is reduced by an order of magnitude.

Abstract: A magnetic wheel driving device and a driving method using the same. The magnetic wheel driving device includes a vehicle body, a guide rail system, at least two magnetic wheel systems and a power system. The guide rail system includes two conductor plates, respectively arranged at two sides of the vehicle body. The at least two magnetic wheel systems are symmetrically arranged at two side walls of the vehicle body. A gap is provided between each magnetic wheel system and the corresponding conductor plate. The power system is configured to drive the at least two magnetic wheel systems to rotate.