Abstract: Provided is a performance controlling method for a high-strength aluminum alloy shell during an ultra-low temperature forming process. The present disclosure greatly improves the performance of an aluminum alloy sheet by applying an ultra-low temperature. The present disclosure cools the aluminum alloy sheet to an ultra-low temperature by using an ultra-low temperature cooling medium, so as to compensate for insufficient hardening caused by insufficient deformation and avoid cracking caused by increased deformation. The present disclosure cools the sheet blank zonally according to a deformation law of a desired curved part, and controls the ultra-low temperature distribution of the sheet blank during forming so as to promote the formation of a substructure in a small-deformation zone. In this way, the present disclosure improves a subsequent age-hardening effect, and corresponding uniformity of microstructure and performance, and effectively solves the problem of non-uniformity due to uneven deformation.

Abstract: A parameter similarity method for test simulation conditions of an aerodynamic heating environment is disclosed. With respect to the requirement that the adiabatic wall enthalpy and the cold-wall heat flux are equal in the simulation test of the aerodynamic heating environment, a method that can ensure the similarity of ground test parameters and flight parameters without the equal adiabatic wall enthalpy is proposed, and solves the problems of relying on the equal adiabatic wall enthalpy and making it difficult to accurately simulate the real aerodynamic heating environment in the current test simulation method, and provides guarantee for heat transfer and ablation test research of thermal protection/insulation material under the high temperature aerodynamic heating environment. The test conditions are not affected by the value of the adiabatic wall enthalpy. According to the method, most test devices can simulate the aerodynamic heating environment with high enthalpy.

Abstract: An experiment system and method for accurate controlling of macromolecular crystallization process. The system has a platform-equipped horizontal moving slot and channel dedicated backwash module, a droplet adding control module, an observing module, a user observation computer system, and an experimental condition control module. A high-precision movement knob of the x-axis platform and the y-axis platform of the system and the accurate position control of a syringe needle are used to ensure that the macromolecular solution can be added into the correct positions of convex or concave. The crystallization induction period of the target crystal form is determined by the real-time data of the high-speed microcamera, and the crystal cultivation environment is adjusted in real time. This is simple and easy to operate, high in productivity, can be applied to the conventional experimental replication.

Abstract: A design method of aero-engine on-line optimization and multivariable control based on model prediction control realizes aero-engine multivariable control and on-line optimization according to thrust, rotational speed and other needs under the condition of meeting constraints. The first part is a prediction model acquisition layer that continuously establishes a small deviation linear model of an aero-engine near different steady state points based on the actual operating state of the aero-engine in each control cycle and external environment parameters and that supplies model parameters to a controller; and the second part is a control law decision-making layer which is a closed loop structure that consists of a model prediction controller and an external output feedback. The model prediction controller determines the output of the controller at next moment by solving a linear optimization problem according to an engine model in the current state, a control instruction and relevant constraints.

Abstract: An electromagnetic drive spherical robotic wrist with two degrees of freedom and a control method therefor, which is particularly a highly integrated active spherical robotic wrist, realizes pitch and yaw rotation with two degrees of freedom under the direct drive of a coaxial following magnetic torque of a spatial universal rotational magnetic field through a built-in permanent magnet cylinder with radial magnetization of a following mechanism formed by coaxial connection of two output ends of internal and external universal joints with the same rotation center. The electromagnetic drive spherical robotic wrist overcomes the disadvantages of a complex transmission mechanical wrist, and a wrist transmission system has a simple and light structure, high transmission efficiency, good static and dynamic performance, and fast control response.

Abstract: Disclosed are a self-righting unmanned ship suitable for adverse sea conditions and a self-righting working mode thereof, belonging to the field of unmanned ship equipment and techniques. The unmanned ship comprises a main hull, a self-righting deck, an equipment and pipeline mast, a propeller, a radar, an air inlet and exhaust system, and a main engine system. Through the design of a watertight deck, the hull of the unmanned ship has a self-righting function, avoiding the possibility of the unmanned ship itself turning over, without installing additional self-righting equipment. Meanwhile, the internal structure and the self-righting working mode of the unmanned ship make it possible for the hull to automatically turn off the main engine and the air inlet and exhaust system when the heeling angle of the hull exceeds a certain angle, making the whole ship watertight.

Abstract: A method for prediction of key performance parameters of an aero-engine transition state acceleration process based on space reconstruction. Aero-engine transition state acceleration process test data provided by a research institute is used for establishing a training dataset and a testing dataset; dimension increase is conducted on the datasets based on the data space reconstruction of an auto-encoder; model parameters optimization is conducted by population optimization algorithms which is represented by particle swarm algorithm; and random forest regression algorithm performing well on high-dimensional data is used for carrying out regression on transition state performance parameters, which realizes effective real-time prediction from the perspective of engineering application.

Abstract: A vehicle capable of taking off and landing vertically and operating in water, land, air and submarine environments includes a fuselage, two main wings, ailerons, a vertical tail, a rudder, a horizontal tail, elevators, a propeller, rotor wings, rotor wing supports, etc. The vehicle has the advantages of adaptability to various environments, good concealment and strong survivability. Compared with a traditional unmanned rotorcraft, the vehicle has longer endurance time and larger load. Compared with a fixed wing UAV, the vertical take-off and landing function makes the work more convenient. Compared with unmanned diving equipment, the vehicle is applicable to richer environments, and can complete designated missions in air, land, water and submarine environments. Compared with a tilt rotor UAV in water, land, air and submarine environments, the vehicle is rapider in switching of various modes and is higher in stability.

Abstract: A toolpath topology design method based on vector field in sub-regional processing for the curved surface is disclosed which comprising: finding the functional relationships in feeding direction between the chord error and the normal curvature and between the scallop-height error and the normal curvature; establishing the bi-objective optimization model and calculating the optimal feeding direction at each cutting contact point within the surface through the constructed evaluation function, the space vector field is built; calculating divergence and rotation of the projected vector field and according to whether them are zeros or not to classify different sub-regions, the primary surface segmentation is achieved, etc. The method is applied for the complex curved surface processing, which can reduce the machining error and enhance the feed motion stability.

Abstract: The present invention provides a cross-axis and cross-point modal testing and parameter identification method for predicting the cutting stability, which is used to improve the accuracy of existing prediction methods of cutting stability. The method firstly installs a miniature tri-axial acceleration sensor at the tool tip, and conducts the cross-axis and cross-point experimental modal tests respectively. The measured transfer functions are grouped according to different measuring axes, and the dynamic parameters are separately identified from each group of transfer functions. Then, the contact region between the cutter and workpiece is divided into several cutting layer differentiators. After that, together with other dynamic parameters, all the parameters are assembled into system dynamic parameter matrices matching with the dynamic model. Finally, dynamic parameter matrices including the effects of cross-axis and cross-point model couplings are obtained.

Abstract: A construction method for a recyclable anchor rod. The recyclable anchor rod includes a reinforcing steel bar body and an unlocking device. The unlocking device includes a housing, a fixed panel, a top limiter, lifting screw limiters, a lifting screw, transmission gears, gear clamping arms, a thread limiter, and a pressure bearing plate. The construction method includes: 1, positioning; 2, drilling; 3, anchoring; 4, performing primary grouting; 5, performing secondary grouting; 6, tensioning and locking; and 7, recycling the reinforcing steel bar body. Shock-absorbing pressure-bearing devices are arranged between the lower end of the housing and the pressure bearing plate.

Abstract: A multi-material inspection system and velocity measurement method of critically refracted longitudinal wave based on single-angle wedges belong to the field of nondestructive testing of high-end equipment. The method includes the following steps: designing a transmitting wedge and a receiving wedge with the same inclination angle, and building phased array ultrasonic-based inspection systems of critically refracted longitudinal wave; estimating a longitudinal wave velocity range of a material to be tested, calculating and optimizing a phased array ultrasonic delay law, and building a relation between a longitudinal wave velocity and an amplitude of critically refracted longitudinal wave; reading and interpolating the arrival time of a received signal, and calculating a longitudinal wave velocity of the material to be tested; determining an optimal delay law, and exciting and receiving a critically refracted longitudinal wave.

Abstract: The invention belongs to the technical field of green chemistry, and provides a novel system based on a new nitrile hydratase for highly efficient catalytic conversion of aliphatic dinitriles. The invention discloses a new application of nitrile hydratase using Rhodococcus erythropolis CCM 2595 in catalyzing aliphatic dinitrile. In particular, the enzyme can regioselectivity catalyze the formation of 5-cyanopyramides from adiponitrile with high reaction rate under mild reaction conditions, which provides a new method for the industrial production of 5-cyanopyramides.

Abstract: An apparatus for efficiently preparing spherical metal powder for 3D printing includes a housing, a crucible and a powder collection area arranged in the housing, wherein a turnplate arranged in the collection area is an inlaid structure. A material having a poor thermal conductivity is selected as the base of the turnplate, and a metal material having a wetting angle less than 90° with respect to droplets is selected and embedded into the base to serve as an atomization plane of the turnplate. An air hole is disposed in the turnplate. The spherical metal powder for 3D printing combines electromagnetic force breaking capillary jet flow and centrifugal atomization, which breaks through the traditional metal split mode, and makes the molten metal in a fibrous splitting.

Abstract: A method and device for manufacturing a large-sized thin-walled tubular part by gas-liquid internal high pressure forming (IHPF). A gas and a liquid are filled at a certain volume ratio into a thin-walled blank. The pressure of the gas-liquid mixed fluid is mainly determined by the gas pressure. During the deformation of the thin-walled blank, due to a large compression ratio of the gas, the gas-liquid pressure will not basically change with the change of the volume of a blank cavity. A support pressure on the cavity of the thin-walled blank is stable in the entire forming process. In addition, even if there is a slight leakage of the liquid or gas during the forming process, the medium pressure inside the blank will not fluctuate largely. In this way, embodiments lower the requirements for the sealing effect during the tubular part forming process.

Abstract: The present disclosure discloses an apparatus and a method for forming a large-scale thin-walled ring shell by hot-press bending with internal gas pressure. The method comprises: welding a first head and a second head to the pipe; arranging a first electrode and a second electrode at the two ends of the pipe; charging compressed gas to the heated sealed pipe assembly; placing the sealed pipe assembly between the convex part of the first die and the concave part of the second die, controlling the temperatures of the first and second dies to perform press bending; increasing the gas pressure in the bent sealed pipe assembly, to attach the bent sealed pipe assembly to the die cavity profile; discharging the compressed gas, cutting the first head, second head and extra material to obtain a formed ring shell segment; welding formed ring shell segments to obtain a large-scale thin-walled ring shell.

Abstract: A floating breakwater and wind energy integrated system used for offshore aquaculture. The system contains the wind turbine system, the floating breakwater system, and offshore aquaculture system. The combination of wind turbine, floating breakwater system and offshore aquaculture system makes full use of the floating breakwater, thus decrease the wave load on the floating cage. In addition, the floating breakwater offers a supporting platform to the floating wind turbine, which effectively reduces the costs of the wind turbine. Meanwhile, a power autarkic offshore aquaculture system may be realized by using the electrical energy generated by the turbine. Compared with the simple offshore aquaculture system, the utilization rate of the sea per unit becomes even higher while the costs of the floating wind turbine becomes even lower.

Abstract: The present invention belongs to the technical field of energy consumption and vibration reduction of assembled building structures, and provides an energy-consuming connecting device for a prefabricated assembled wall. The present invention provides a normal connection function between walls, and also has the functions of energy consumption and vibration reduction. A used viscoelastic material can provide energy consumption and weaken the cold and hot bridge effect, which is beneficial to building thermal insulation. Meanwhile, the energy-consuming connecting device for the prefabricated assembled wall can be connected with a prefabricated wall in advance, which can be carried out at the same time as the wall is inserted during construction, thereby effectively increasing the construction efficiency. Through the design of clamping groove devices, the wall can be connected firmly and reliably while generating displacement and consuming energy.

Abstract: The wind-wave complementary energy integrated system based on fixed foundation and generation and transmission method thereof pertains to the field of ocean renewable energy utilization, solving the problem of combining the wind and wave energy in a support structure, including a wind turbine, a tower, a wave energy device and a single pile foundation, the wind turbine is connected to the tower, and the single pile foundation is at the bottom of the tower, the single pile foundation is connected to the seabed, and the wave energy device is mounted on the tower near the sea surface. The effect is the renewable energy utilization rate and the energy conversion rate are effectively improved, thus reducing the cost to a certain extent and having high utility.

Abstract: The present invention relates to a free-sliding seabed mudmat foundation, which belongs to the fields of offshore and ocean engineering. The mudmat comprises a base foundation, an upper foundation, and a cover plate. The base foundation sits on the seabed to support dead weights of the mudmat itself and the subsea production system fixed on the mudmat. The upper foundation, with a plurality of universal rolling ball bearing being attached to the bottom, can slide on the base foundation when it is subjected to a horizontal push force generated by the pipeline during operation. Therefore, the axial load on the pipeline during operation due to heating and pressurization is released and the buckling failure risk is then reduced. The mudmat disclosed has smaller size and lighter weight, which is beneficial in reducing fabrication costs and reducing requirements for cranes on the pipeline laying vessel.