Abstract: A low-complexity selective mapping method using cyclic redundancy check is provided. In performing coding, a transmitter adds a check bit to information bits to be transmitted to obtain modulated data. Demodulation is performed on an M-order modulation symbol received by a receiver to obtain a decoding result of a coding polynomial of the modulation symbol and bit information received by the receiver. A modulo-2 division result of the decoding result of the coding polynomial and a generation polynomial is calculated. In a case that a remainder of the modulo-2 division result is equal to zero, if the modulated data corresponding to the same index value of the receiver and the transmitter are identical, a current iteration is stopped, and a current value is outputted as a phase rotation sequence index recovery value. Finally, the receiver obtains a decoded signal.

Abstract: The present disclosure provides a hydrogen evolution electrode and a preparation method thereof. The preparation method includes the following steps: providing an electrolyte including Co(NO3)2·6H2O with a Co(NO3)2 concentration of 0.005 mol L?1 to 0.015 mol L?1, MnCl2·4H2O with a MnCl2 concentration of 0.005 mol L?1 to 0.01 mol L?1, KCl with a concentration of 0.003 mol L?1 to 0.008 mol L?1, and CH3CSNH2 with a concentration of 0.04 mol L?1 to 0.06 mol L?1; adjusting the electrolyte to a pH value of 6 to 7; providing a cathode in the form of a substrate; and conducting electrolysis in a cyclic voltammetry mode, thereby preparing the electrode for hydrogen production by water electrolysis through electrochemical deposition of a Co9-xMnxS8 nanosheet catalyst on the cathode substrate, where 1?X?7.

Abstract: The invention relates to a method for preparing amorphous particle-modified magnesium alloy surface-gradient composites and pertains to the technical field of composites. The method comprises steps of: holding the temperature at 150˜350° C. for FeCrMoBC amorphous alloy particles; mixing pure magnesium, pure zinc, pure aluminum, pure copper and Mg-5 wt % Mn alloy under continuous protective gases, gradually raising temperature to 720˜760° C. and melting at a constant temperature for 15˜25 min to obtain a magnesium alloy melt; cooling the magnesium alloy melt to 600˜635° C. and starting mechanical stirring; continuing the cooling until the semi-solid temperature is 570˜615° C., slowly adding the above FeCrMoBC amorphous alloy particles, holding for 2˜5 min after mixing evenly, and cooling the crucible with water to obtain an amorphous particle-modified magnesium alloy surface-gradient composite.

Abstract: A distributed computation offloading method based on computation-network collaboration in a stochastic network is provided. The distributed computation offloading method includes: building a device revenue maximization problem model and a MEC server revenue maximization problem model based on a local computing model and an edge cloud computing model; building composite sets of scenarios for dwell time and waiting latency based on a random movement of a user and burst computation demands; compensating for a game strategy by using a posteriori recourse action and building a game-based stochastic programming model between the device and the MEC server; transforming a multi-stage stochastic regularization problem for both the device and the MEC server into a DEP problem by constructing a scenario tree, and solving the DEP problem to obtain an optimal task strategy for the offloading from the MEC server and an optimal offering strategy of the MEC server to the device.

Abstract: Disclosed are a method and a device for obtaining a safe interval of a human body parameter in a built environment, a terminal device, and a storage medium. The method includes: obtaining a first facial image, a benchmark human body parameter, and a human body posture analysis result of a target user in a target built environment; inputting the first facial image into an emotion analysis model to obtain an emotion analysis result; and obtaining the safe interval of the human body parameter of the target user according to the emotion analysis result, the human body posture analysis result, and the benchmark human body parameter.

Abstract: A time series data adversarial sample generating method and system, an electronic device, and a storage medium, relating to the field of time series data processing. The method comprises: training a time series prediction model using original time series data (101); calculating a maximum value of a loss function in the time series prediction model by means of a stochastic gradient descent optimization strategy (102); determining corresponding noise according to the maximum value of the loss function (103); and superimposing the noise on the original time series data to generate a globally disturbed time series data adversarial sample (104). The method can significantly reduce the model accuracy under the condition of a small amount of data disturbance, has important significance for safe application of an industrial system, and has wide applicability and transferability.

Abstract: The present invention relates to the field of digital signal processing, and in particular to a Costas sequence time-frequency joint synchronization method based on all-phase spectrum correction. The method improves the defects existing in a discrete frequency spectrum correction algorithm using short-time Fourier transform and sliding correlation. The improvement mainly comprises: the present disclosure provides a solution based on iterative optimization: when an actual frequency offset is an integral multiple of the spectral resolution, a large error can occur, frequency offset correction and time delay correction are carried out on a signal by using an estimated value having a large estimated error, then estimation is carried out again, and the frequency offset of the signal is not a special value by means of an iteration mode.

Abstract: The present disclosure relates to a dual-band antenna array with fan beam and pencil beam. The antenna comprises a substrate and an antenna array arranged on the surface of the substrate, a first antenna element and a second antenna element are cascaded in an x-axis direction by a filter phase-shift line so as to form a subarray. A pair of T-shaped monopoles are symmetrically placed along the x axis at a certain distance above and below each of the first and second antenna elements, respectively, and a rectangular slot is embedded in the upper edge of the second antenna element to achieve good impedance matching. The second antenna element generates a fan beam at one frequency point or frequency band to have the performance of a wide beam, and generates a pencil beam at another frequency point or frequency band to have the performance of a narrow beam.

Abstract: Disclosed is a method for identifying secondary reservoir formation boundaries and combined extraction of multiple asymmetric mining coalbed methane. This method fully combines the displacement transfer mechanism after multiple mining to determine its influence on a horizontal thrust of overlying strata after a first mining, and then determines evolution characteristics of pressure arches. Combining the identification of different types of pressure arches with a layout of a surface well accurately determines a secondary reservoir formation range of coalbed methane. By adopting the method of mining face overlying strata in series for combined extraction, coalbed methane from multiple mine faces is extracted by one well to greatly improve the coalbed methane extraction effect.

Abstract: A method for image processing, which comprises the following steps: Generating a first histogram from a first image; Calculating a first parameter profile from the first image indicative of the quality of the first image; Adjusting the first parameter profile to generate a second parameter profile; Using the second parameter profile to generate a statistical distribution via a statistical distribution generator, wherein the statistical distribution is characterized by at least three parameters; Using the statistical distribution to perform a histogram specification to the first histogram of the first image to generate a second histogram; Generating a second image based on the first image and the second histogram.

Abstract: The present disclosure discloses a control device for bridge vortex vibration comprising a control unit arranged at a bottom of a bridge. The control unit includes several controllers which include a base and several sliding sheets. The base is formed with a sliding groove along the length direction. A wedge block is slidably provided in the sliding groove. Each side of two sides of the base is provided with several sliding holes. Each of the sliding sheets is arranged in a corresponding one of the sliding holes. An end of each of the sliding sheets is provided with a wedge surface matched with the wedge block. A bottom of each of the sliding sheets is provided with a wind shielding structure. The object of the disclosure is to solve the technical problem of possible vortex vibration of a bridge under the condition of a low wind speed.

Abstract: The present disclosure provides a method for predicting a remaining useful life (RUL) of an aero-engine, specifically including: acquiring multidimensional degradation parameters of an aero-engine to be predicted to obtain acquired data; segmenting the acquired data by a sliding window (SW) to obtain preprocessed data; constructing a RUL prediction model of the aero-engine including a multibranch convolutional neural network (MBCNN) model, a multicellular bidirectional long short-term memory (MCBLSTM) model, a fully connected (FC) layer FC1, and a regression layer; taking the preprocessed data as input data of the MBCNN model, extracting an output of the MBCNN model, taking the output of the MBCNN model and recursive data as input data of the MCBLSTM model, and extracting an output of the MCBLSTM model; obtaining an output of the FC layer FC1, and inputting the output of the FC layer FC1 to the regression layer to predict a RUL.

Abstract: The present application discloses a nanometer self-locking bentonite film-forming agent, a method for preparing the same, and a film-forming drilling fluid.

Abstract: Provided is a data security sharing method for multiple edge nodes to operate in a collaboration mode under an industrial cloud environment. The method includes: firstly, edge nodes that need collaborative computing separately applying for a shared key to an authority center; secondly, the authority center generating a shared key and issuing the key to each of the edge nodes applying for participation in the collaborative computing; again, the edge nodes combining industrial characteristics to generate an interference factor set, and adding different interference factors for different types of data; then, the data of the edge nodes is implemented with improved homomorphic encryption and is uploaded to an industrial cloud platform; and finally, the industrial cloud platform performing homomorphic analysis and computing on the data uploaded by each of the edge nodes, and issuing the data back to each of the edge nodes.

Abstract: The present disclosure discloses a method for quick weighing of loose and small packages of traditional Chinese medicine (TCM), comprising: 1) establishing an equivalent physical model of a weighing system for loose and small packages, and, through Laplace transformation and Z transformation, obtaining a formula of the mass M of medicine packages to be weighed; 2) calculating a1, a2, b1 and b2 on the basis of a vector prediction error; 3) according to a1, a2, b1, and b2 obtained and the formula of the mass of medicine packages to be weighed, obtaining the mass of the loose and small packages of TCM that are weighed. According to the method, the scalar prediction error is expanded into the vector prediction error based on the traditional method so as to construct a new identification model based on the vector prediction error, and as a result the utilization efficiency of prediction error turns higher.

Abstract: A test piece holder for coalbed fracturing comprises a pressure chamber, first sliding rods, second sliding rods, third sliding rods, fourth sliding rods, fifth sliding rods, oil cylinders and a sealing ring, upper and lower ends of a test piece are both provided with an electrode needle and a gas-guide and liquid-guide conducting bolt, the gas-guide and liquid-guide conducting bolt has a hollow rod structure, an inside end of the gas-guide and liquid-guide conducting bolt located above is communicated with a water-gas channel and an outside end of the gas-guide and liquid-guide conducting bolt located above is a water-gas outlet, an inside end of the gas-guide and liquid-guide conducting bolt located below is communicated with the water-gas channel and an outside end of the gas-guide and liquid-guide conducting bolt located below is respectively provided with a gas inlet and a water inlet.

Abstract: The present disclosure provides a preparation method of a plasma-treated nanofiber-based hydrogen gas sensing material, including the following steps: (1) stirring a mixed solution of absolute ethanol, polyvinyl pyrrolidone (PVP), N, N-dimethylformamide, SnCl2.H2O, and Zn(CH3COO)2.2H2O uniformly on a constant-temperature magnetic stirrer to obtain a spinning solution; (2) electrospinning the spinning solution and depositing on an aluminum foil to obtain a spinning fiber; (3) annealing the spinning fiber in a muffle furnace to obtain a hydrogen gas sensing material sample; and (4) subjecting the hydrogen gas sensing material sample to a vacuum argon plasma treatment with a Hall ion source to obtain the nanofiber-based hydrogen gas sensing material. In the method, nanofibers are prepared by electrospinning and subjected to the vacuum argon plasma treatment through the Hall ion source.

Abstract: A method for predicting a remaining life of a tool of a computer numerical control machine is provided. In the method, indirect measurement indicators of the tool are selected based on monitoring and analyzing a current state of the tool, a prediction model for the remaining life of the tool is established based on data de-noising, feature extraction and a multi-kernel W-LSSVM algorithm. Thereby, a method for predicting a remaining life of a tool of a computer numerical control machine is provided.

Abstract: Disclosed is an environment forming apparatus suitable for biological cultivation in extraterrestrial space. The apparatus includes a shell and a biological cabin configured in an upper space of the shell. A light management system for importing light of biological growth from external world is configured in the upper space, a thermal management system for at least balancing a temperature of the upper space and a water supplying system and configured for providing water for creatures growth are both configured on the shell. The biological cabin and the like are set at the appropriate part of the shell, an environment which is relatively suitable for biological growth or cultivation can be created and simulated on an extraterrestrial star, a condition is provided for ecological cultivation of the extraterrestrial space, an ecosystem of the extraterrestrial space can be formed, and a smooth extraterrestrial space biological experiment process is guaranteed.

Abstract: The present disclosure provides an automatic test card for a multi-blood group system and a test method. The test card of a multi-blood group system includes four parts from top to bottom: a sample loading layer, a reaction layer, a color developing layer, and an identification layer. The automatic test card for a multi-blood group system and the test method combines blood group detection with encoding, and can rapidly and automatically identify and test multiple blood groups, reduce manual judgment errors, and improve detection efficiency. The method does not require special equipment and achieves rapid, accurate, automated, and portable detection of the blood groups.