Abstract: Some embodiments of the disclosure disclose a space assembly system based on fusion of on-orbit additive manufacturing and ground-based launch. In some examples, an operator establishes a space manufacturing center to achieve on-orbit manufacturing of spacecraft structural components and assembles the components manufactured on orbit with spacecraft enabling modules launched from the ground to form a target spacecraft. The system includes a physical subsystem, a digital twin subsystem, and a communication subsystem. The physical subsystem includes a control unit, a communication unit, a sensor unit, an imaging and positioning device, a data storage unit, a data processing unit, an additive manufacturing unit, a space robot unit, and a raw material bin. The digital twin subsystem remotely monitors the physical subsystem. The communication subsystem establishes a connection between the physical subsystem and the digital twin subsystem and a connection between all units and devices of the physical subsystem.

Abstract: Provided are a device and a method for measuring pore size distribution of porous media through a harmonic analysis. The device includes a signal application system, instruments for measuring pressure and displacement, a signal processing instrument and a sample and fluid storage container. According to the disclosure, an oscillating flow is applied to a sample through the signal application system, pressure and displacement signals are collected by the signal processing instrument, a harmonic analysis is performed on the signals, and a frequency response of admittances of the porous media is calculated according to harmonic analysis results of the signals, so that the pore size distribution is obtained.

Abstract: Some embodiments of the disclosure disclose a space assembly system based on fusion of on-orbit additive manufacturing and ground-based launch. In some examples, an operator establishes a space manufacturing center to achieve on-orbit manufacturing of spacecraft structural components and assembles the components manufactured on orbit with spacecraft enabling modules launched from the ground to form a target spacecraft. The system includes a physical subsystem, a digital twin subsystem, and a communication subsystem. The physical subsystem includes a control unit, a communication unit, a sensor unit, an imaging and positioning device, a data storage unit, a data processing unit, an additive manufacturing unit, a space robot unit, and a raw material bin. The digital twin subsystem remotely monitors the physical subsystem. The communication subsystem establishes a connection between the physical subsystem and the digital twin subsystem and a connection between all units and devices of the physical subsystem.

Abstract: Some embodiments of the disclosure provides an intelligent modularized reconstruction system for a spacecraft based on analysis of a task text. In some examples, the intelligent modularized reconstruction system includes a modularized spacecraft component library, a modularized spacecraft component recommendation subsystem, a target spacecraft generation subsystem, and a three-dimensional simulation environment. In other examples, for a new spacecraft reconstruction task, the modularized spacecraft component recommendation subsystem recommends a type and a quantity of required modularized components from the modularized spacecraft component library for input task text. Each modularized component recommended by the modularized spacecraft component recommendation subsystem is used to generate three-dimensional model data of a target spacecraft by the target spacecraft generation subsystem. The three-dimensional simulation environment displays the generated three-dimensional model data of the target spacecraft.

Abstract: An observable micro-nano mechanical testing apparatus and an observable micro-nano mechanical testing method are provided. The apparatus includes a supporting component, a driving component, a bearing component and an imaging component. The driving component and the imaging component are respectively vertically arranged on the supporting component, the bearing component is horizontally arranged on the supporting component and positioned below the driving component and the imaging component, the bearing component is used for bearing a sample and moving the sample, the driving component is used for driving an indenter to apply loads on the sample so as to form an indentation on the sample, and the imaging component is used for observing and analyzing the indentation on the sample.

Abstract: A PMSM sensorless composite control method with dual sliding-mode observers is provided. In particular, two sliding-mode observers are designed, one provides an exponential piecewise sliding-mode function for observation of back electromotive force, and the other sliding-mode observer is for observation of load torque and fine-tuning parameters of a piecewise PI controller while introducing an estimated load torque onto a q-axis for feedforward compensation. A q-axis current inner loop is designed with a second-order sliding-mode controller, which can improve tracking performance of q-axis current and indirectly control an electromagnetic torque. The exponential piecewise sliding-mode function is more conductive to the observation of back electromotive force and can weaken the buffeting phenomenon. The sliding-mode observer for observing the load torque fine-tunes parameters of the piecewise PI controller while performing the feedforward compensation, the load capability of the system is improved.

Abstract: The present disclosure discloses an observable micro-nano mechanical testing apparatus and method. The apparatus includes a supporting component, a driving component, a bearing component and an imaging component. The driving component and the imaging component are respectively vertically arranged on the supporting component, the bearing component is horizontally arranged on the supporting component and positioned below the driving component and the imaging component, the bearing component is used for bearing a sample and moving the sample, the driving component is used for driving an indenter to apply loads on the sample so as to form an indentation on the sample, and the imaging component is used for observing and analyzing the indentation on the sample. Based on the testing method conducted by the testing apparatus in the present disclosure, mechanical property parameters of materials can be effectively measured; the structure is simple; and accuracy of measurement results is high.

Abstract: Disclosed is a method and system for determining a motion path of a mechanical arm in which, after a kinematics model of a mechanical arm is established, multiple objective optimization functions are constructed according to the model, theoretical coordinates of a tail end of the arm, and an arm length. If a number of individuals in an evolutionary population, that makes both lateral and longitudinal error optimization functions in an optimization function monotonically increase or decrease, reaches the threshold, an optimal solution is determined using a single-objective evolutionary algorithm; otherwise, a multi-objective evolutionary algorithm is used. The multi- or single-objective evolutionary algorithms can be adaptively selected according to the number of individuals in the population that makes the lateral and longitudinal error optimization functions change.

Abstract: Disclosed is a method and system for splicing and restoring shredded paper based on an extreme learning machine (“ELM”). The method includes: acquiring a shredded paper training sample to be spliced; extracting left and right boundary feature data of the sample; training an ELM neural network model according to the feature data to obtain a trained neural network model (“TNNM”); acquiring a shredded paper test sample to be spliced; extracting feature data of the test sample; selecting a first piece of to-be-spliced shredded paper; selecting, by the TNNM, a shredded piece with a highest degree of coincidence with the first piece; determining whether the shredded piece is correctly spliced to the first piece; if yes, splicing shredded paper until all shredded paper is spliced and restored; if not, adopting manual marking, and continuing to select, by the TNNM, shredded paper with a highest degree of coincidence with the first piece.

Abstract: A dyeing color matching method and system based on a preference genetic algorithm includes: obtaining a reflectivity of a color scheme sample and a first color scheme set having N color schemes; initializing the first color scheme set using a preference genetic algorithm to obtain an initialized color scheme set; conducting crossover and mutation on any two color schemes in the initialized set to obtain a second color scheme set having 2N color schemes; substituting the color schemes in the second set into the conventional model to obtain 2N model reflectivities; determining a third color scheme set according to the 2N model reflectivities; determining whether a color scheme that satisfies a customer's requirement exists in the third set; if yes, conducting proofing on the color scheme to obtain a proofing color scheme set; and determining a color scheme with a minimum color difference according to the proof color scheme.

Abstract: A method for recovering and purifying a waste sulfuric acid solution includes steps of: adding a coupling agent (m) to the waste sulfuric acid solution, and mixing uniformly to obtain a mixture (a); adding a coupling agent (n) to the mixture (a), and mixing uniformly to obtain a mixture (b); and adding a synergistic agent to the mixture (b), thoroughly stirring and filtering to obtain a purified sulfuric acid solution. The method adds the coupling agent and the synergistic agent to the waste sulfuric acid, and a removal rate of the heavy metal ions in the waste sulfuric acid can reach 99%. The purified sulfuric acid solution can be recycled. The method is simple to operate, and can remove a wide variety of heavy metal ions such as copper, zinc, lead, mercury, nickel, iron, cadmium and manganese in the waste sulfuric acid.

Abstract: Provided is a microwave catalyst. The microwave catalyst comprises: i) an active catalyst component comprising a metal and/or a metal oxide; ii) a microwave-absorbing component comprising at least one of CuO, ferrite spinel, and active carbon; and iii) a support. The microwave catalyst can be used for denitration by microwave catalysis, and has advantages such as high denitration efficiency, low energy consumption, environmental friendliness, and low costs. Also provided is a process for preparing the microwave catalyst and the use thereof.