103results about How to "Good engineering practicability" patented technology

The invention relates to a spacecraft attitude integral sliding mode fault tolerance control method taking consideration of a performer fault and provides a robustness attitude active fault tolerance control method based on an integral sliding mode surface for problems of the performer fault, external disturbance and control moment amplitude limits in a spacecraft attitude control process. The method comprises steps that firstly, a spacecraft attitude dynamics model taking consideration of the performer fault and containing external disturbance is established; secondly, on the condition that a performer is not in fault, a designed nominal controller can guarantee system stability, and input saturation amplitude limits can be easily satisfied through adjusting controller parameters; lastly, the fault information is introduced to design an integral sliding mode controller, robustness of external disturbance and the performer fault can be effectively improved, system stability is analyzed on the basis of an Lyapunov method. The method is advantaged in that stability of the attitude control system is guaranteed when a spacecraft operating on orbit generates the performer fault, and relatively strong fault tolerance capability and external disturbance robustness are realized.

The invention provides a photovoltaic power prediction method based on a ground-based cloud chart. The method comprises the following steps: 1) pre-estimating the movement of a cloud cluster; 2) predicting irradiance on the ground; 3) establishing a comprehensive photoelectric conversion model; 4) and carrying out photovoltaic power prediction. A plurality of digital picture processing techniques are comprehensively applied, so that requirements of problems are highlighted, pertinency and practicality are high, and combined with the traditional statistical method, the photovoltaic power prediction method provides effective technical support and method reference for a photovoltaic power refinement prediction; models are established with multi-steps based on synthesizing of multi-factors; key links in the photovoltaic prediction field are all included in the description of the method, so that universality and robustness are high; in order to combine concrete scenes and application objects used during usage, adjustment parameters are reserved in some links, so that operation is convenient and prediction effect is guaranteed.

The invention discloses a hybrid energy storage system and a wind power generation power smooth control method. Firstly, a frequency spectrum of a wind power signal is obtained through a quick Fourier method, and amplitude-frequency characteristics of wind output power are analyzed; then, wind power is decomposed in multiple scales through an empirical mode decomposition method and then reconstructed into wind farm expected grid-connection power and high-frequency, mediate-frequency and low-frequency wind power fluctuation power; the power is distributed according to the capacity of a super-capacitor Soc, correspondingly adjusted and absorbs high-frequency, mediate-frequency and low-frequency fluctuation signal power through the super-capacitor, a storage battery and stored compressed air energy; when the output power of a wind farm is smaller than an expected grid-connection power signal, a hybrid energy storage system composed of the super-capacitor, the storage battery and an CAES is controlled to discharge through a model algorithm; when the output power of the wind farm is larger than expected grid-connection power, the hybrid energy storage system composed of the super-capacitor, the storage battery and the CAES is controlled to charge through the model algorithm. The hybrid energy storage system and the wind power generation power smooth control method improve safety and economic efficiency of grid-connection operation.

The invention relates to a time-varying rotational inertia considered adaptive fault tolerance control method of spacecraft attitude. The method comprises that a dynamic spacecraft attitude tracking model which does not take faults of a performer into consideration but includes external disturbance and a time-varying rotational inertia is established, and a time-varying rotational inertia model isestablished; and on the basis of the dynamic spacecraft attitude tracking model, a nominal controller and corresponding adaptive laws are designed, and the system stability and tracking error convergence without faults are ensured; and the performance fault is added to the dynamic spacecraft attitude tracking model, an auxiliary controller is designed on the basis of the nominal controller, the problem that a fault occurs in the performer, the time-varying rotational inertia exists and the spacecraft is influenced by an external disturbance moment during on-orbit work of the spacecraft is solved, and the fault tolerant capability and robustness of the system are ensured.

The invention provides a cloud cluster movement estimation method facing to photovoltaic power prediction. The cloud cluster movement estimation method for the photovoltaic power prediction comprises the following steps: preprocessing an image of a ground-based cloud picture; thresholding the ground-based cloud picture; detecting and marking a cloud cluster and extracting center of mass of the cloud cluster; and estimating moving speed and direction of the cloud cluster. By the cloud cluster movement estimation method for the photovoltaic power prediction, each cluster in a time sequence image is tracked and studied to determine the moving speed and direction of the cloud cluster in the future, so that the cloud cluster movement in the future is estimated, and an important data source is provided for minute-grade power prediction within a super-short period of 0-4 hours for a photovoltaic power station.

The present invention relates to a radar application-based target RCS real-time evaluation method. According to the method, firstly, echo signals are subjected to AD sampling and digital signal processing, and then original track points are outputted. Secondly, original track points are subjected to coagulation treatment and coagulated track points are subjected to flight track treatment. In thisway, track points are obtained. Thirdly, the amplitude of track points is subjected to distance and STC correction, and the amplitude value of an outputted flight track is subjected to real-time meanstatistics. According to the region of the statistical result of the amplitude mean of a target flight track, the RCS value of the target is estimated. The method can be applied to the RCS real-time evaluation of a to-be-tested target based on radar equipment and is applicable in engineering application conditions.

The invention discloses a spacecraft attitude output feedback tracking control method giving consideration to limited control. Aiming at a problem that the angular speed information cannot be measured directly when a spacecraft works in orbit, and a problem of external disturbance and a problem of limited control, the invention proposes an attitude tracking output feedback controller design method, which has no angular speed information feedback and meets the requirement of limited control input. The method comprises the following steps: firstly building a spacecraft attitude tracking error dynamical model comprising external disturbance; secondly designing a dynamic angular velocity observer; and finally designing an output feedback control method meeting the requirement of limited control input based on angular velocity estimation information through employing the characteristics of a saturation function. The method achieves the independent design of the angular velocity observer of a spacecraft attitude control system and the decoupling of the controller, can achieve the effective online estimation of the angular velocity information, is robust for the external disturbance and limited input saturation, and is suitable for a moving object attitude tracking control system when a spacecraft works in orbit.

The invention discloses a dynamic equivalence method of an alternating-current-direct-current serial-parallel large power system based on engineering application, and belongs to the field of electric transformation and distribution. The method of the alternating-current-direct-current serial-parallel large power system based on the engineering application comprises dividing a power grid to be analysed into two parts including an external power grid and an internal power grid, detailedly imitating a 500 kV power grid inside an area, carrying out equivalence simplification on the external power grid and an internal low voltage power grid, obtaining an external simplified power grid from the external power grid through an equivalence generator by using a dynamic equivalence method based on experience, obtaining a final internal simplified power grid by carrying out equivalence simplification on the internal low voltage power grid by using the dynamic equivalence method based on physical equivalent, respectively checking equivalence effects after the external power grid and the internal power grid are in dynamic equivalence, and checking effectiveness of the entire dynamic equivalence principle and method through comparing dynamic response curves of a simplified power grid and an actual power grid in the same fault. The method of the alternating-current-direct-current serial-parallel large power system based on the engineering application has the advantages of reducing quantity of equivalence system state and the number of differential equation, improving system analysis computational efficiency, and being capable of being widely used for analytical calculation of a serial-parallel large power grid and used in the field of dispatching management of power grids.

The invention discloses a synchronizer gear engagement process control method based on a unilateral pressure control system. On the premise of meeting the power requirement of a driver, according to the conditions of high requirement for matching precision of the synchronizer pressure control logic, differentiation of controlling different boxes through the same matching parameter and the complexity of the actual working conditions, the failure frequency of gear engagement of a synchronizer can be reduced, the working efficiency of the synchronizer is improved, gear engagement impact is small,no obvious noise is generated, the service life of the synchronizer is prolonged, and the method has good engineering practicality.

The invention discloses a mechanical arm robust optimization design method based on interval and bounded probability hybrid uncertainty. The method comprises the following steps: considering two kindsof uncertainty of interval and bounded probability distribution influencing the mechanical arm performance, describing the bounded probability distribution as a random variable obeying generalized beta distribution, and establishing a mechanical arm robust optimization design model; direct solution is carried out based on a genetic algorithm; the robustness of a population individual constraint performance function is analyzed by utilizing the uncertainty boundness, and the feasibility of individuals is judged; for a feasible individual, calculating a mean value and a standard deviation of anobjective function of the feasible individual by adopting a Monte Carlo method based on multi-layer encryption Latin hypercube sampling; and then sorting the individuals of the current population according to the total feasible robustness index and the negative ideal solution approaching distance of the constraint performance function to obtain robust and optimal mechanical arm parameters. The mechanical arm robustness optimization model established by the method truly reflects uncertainty distribution, the optimization process is intelligent and efficient, and the method has good engineeringapplicability.

The invention discloses an array antenna phase-only transformation beam shaping method, which implements beam shaping with different radiation requirements only by phase weighting under a condition that the power keeps unchanged. The method comprises the following steps: obtaining element excitations corresponding to directional diagrams which meet respective radiation performance requirements by employing an improved iterative Fourier algorithm, and retaining each unit phase excitation value corresponding to each type of beams therein; and then, finding a common unit excitation current value by employing an improved convex optimization algorithm to meet higher radiation performance requirements of each directional diagram, such as a smaller main lobe wave in each directional diagram, a lower side-lobe level value and the like. A hybrid optimization algorithm disclosed by the invention effectively combines the iterative Fourier algorithm and the convex optimization algorithm, does not need parameter adjustment and has the characteristics of strong robustness, fast computation speed and high precision, thereby finally implementing simplification of a feed network; and only through a phase excitation change of array elements, the beam shaping with the different radiation performance requirements is implemented.

The invention discloses an efficient recognition method for the flight control signal of a low-altitude, slow-speed and small unmanned aerial vehicle. The method comprises the steps of step 1, carrying out primary detection on a flight control link signal; step 2, extracting key features, and constructing a target feature database; step 3, carrying out feature fusion and optimization; step 4, analyzing the signal according to the fused optimized features so as to obtain the type, the frame format and the keyword segment of the signal, and storing the obtained analysis result into the target feature database; step 5, according to a learning algorithm based on a neural network, realizing the accurate classification and recognition of the target, and obtaining a correct recognition result. According to the method, the recognition problem for the flight control signals of low-altitude, slow-speed and small unmanned aerial vehicles can be solved. Therefore, the recognition, management and control for a specific airspace can be realized. Meanwhile, the high-efficiency early warning and defense effect for various low-altitude, slow-speed and small unmanned aerial vehicles which have illegally intruded into secret-related and sensitive airspaces can be realized. The method is higher in correct recognition rate, lower in calculated amount, higher in processing efficiency and strong in applicability.

The invention discloses a core loading method of pressurized water reactor nuclear power plant first cycle. A first cycle core adopts a fuel assembly with 4-6 different enrichment degrees, a high leakage loading mode is adopted, and core reactivity inhibition and power distribution control are carried out by simultaneously adopting borosilicate glass solid inflammable poison rods and integrated gadolinium-supported fuel rods. The method greatly prolongs the cycle length of the first cycle core, adopts two solid inflammable poisons to avoid the contradiction of occupation of control rod guiding tubes due to use of too much borosilicate glass and avoid negative influences of unfavorable axial power distribution caused by use of too many integrated gadolinium solid inflammable poisons on running control, makes the core design be flexible, makes the power distribution flattening of the core be easy, has good engineering practicality and design flexibility, and can well realize the economy and safety of the power plant.

The invention discloses a low-energy planetoid precise track transfer detection method for complex constraints, and belongs to the technical field of aerospace. The method comprises the steps that firstly, various complex non-consistent strong coupling constraints needing to be met by a track detection design task are determined, and the mapping relation between track design parameters and the various complex non-consistent strong coupling constraints is built; under a mass center rotating coordinate system, a detector dynamics equation is built; an initial value is provided through the builtlinear detector dynamics equation, a precise quasi periodicity track under an ephemeris model is obtained by adopting a nonlinear dimension reduction method and second-order differential coercion; onthe basis of the precise quasi periodicity track under the ephemeris model, a quasi manifold disturbance method is adopted for optimizing the obtained transfer track initial value; for the various complex non-consistent strong coupling constraints, the obtained transfer track initial value is corrected, and the precise low-energy transfer track is obtained. The method has the advantages of being high in efficiency, good in convergence and low in energy needed by transfer.

The invention belongs to the Internet of Things and smart city building field, to be specific, relates to a parking stall detection method based on a geomagnetic sensor. Compared with the prior art, the parking stall detection method gives more considerations to factors affecting parking stall detection results, and therefore the accuracy of the parking stall detection is improved, and good engineering practicability is provided. An artificial neural network is combined with a comprehensive detection algorithm of a network database, and then problems such as the instable detection state of the geomagnetic sensor caused by high sensitivity, fundamental frequency drift of a detected vehicle caused by the long term installation of the geomagnetic sensor on a lane, and the compensation of the geomagnetic sensor caused by large influences of temperature on the geomagnetic sensor, and interferences of different passing vehicles are solved, and therefore the precision and the accuracy of the parking stall detection are improved.

The invention discloses a press machine upper beam robust optimization design method based on a negative ideal solution approaching distance. The method comprises the following steps: considering randomness of loads borne by an upper cross beam of a press machine and interval uncertainty of material attributes of the upper cross beam, and establishing a robust optimization design model for upper beam with random-interval mixed uncertainty variable based on a 6 sigma robustness design principle;directly solving the optimization model based on a double-layer nested genetic algorithm; enabling the inner layer to perform interval robustness analysis on each design vector by using a Kriging prediction model, and calculate a mean value and a standard deviation of the target function and each constraint performance function by using a Monte Carlo method; and enabling the outer layer to use an inner layer calculation result, and classify sort and optimize all the design vectors based on the constraint performance function total feasible robustness coefficient and the negative ideal solution close distance. The method conforms to engineering practice, subjective interference is avoided, andgood engineering practicability is achieved.

The invention provides a cabin cross section circumference measuring device and method based on the non-contact profiling method, and belongs to the technical field of manufacturing and precision measurement. The cabin cross section circumference measuring device comprises a system of a part to be measured, a reference coordinate motor system, a follow-up rocker system and a data collecting, analyzing and processing system. The follow-up rocker system comprises a displacement sensor, a rocker arm, a ball screw, a sliding block, a follow-up servo motor and a counter weight. The data collecting, analyzing and processing system comprises a signal transformer, an analog-to-digital converter, a motion controller and a digital-to-analog converter. The motor drives a rocker arm system to rotate by a circle, the displacement sensor records the coordinate positions of all points to be measured by the adoption of the non-contact method, the shape of the part to be measured is profiled, and the circumference of the part to be measured is calculated. The cabin cross section circumference measuring device and method based on the non-contact profiling method can achieve higher measurement accuracy and cannot scratch the part to be measured at all.

The invention discloses a low-voltage distribution network line loss calculation method based on the influence of the imbalance of three phases on line loss. The method comprises the following steps: according to the load terminal monitored data, calculating the average load current value across the first end of the line; based on the monitored sub-meter current amount, calculating the equivalent resistance of the low-voltage distribution line; according to the data acquired in real time, calculating the imbalance degrees of the single phase and the three phases; and calculating the line loss.

The invention relates to a rapid scaffold connecting device and a construction method thereof. The rapid scaffold connecting device comprises a stand column which is sleeved with a ring disc connected with the ends of a plurality of transverse rods, U-shaped ends clamped to the ring disc are fixedly connected to the ends of the transverse rods, and the U-shaped ends and the ring disc are fixedly connected through bolts A and nuts A; and the stand column is further sleeved with a positioning ring buckle located below the ring disc to limit gliding of the ring disc. The rapid scaffold connecting device is large in rigidity, high transverse rod transmitting loads can be borne, the eccentricity effect is avoided during stressing, the stress performance is good, safety is high, and the overall stability of a scaffold is greatly improved; and rapid mounting and demounting of the scaffold can be achieved, the construction speed is high, and needed manpower is less.

The invention provides a pedestrian mask wearing real-time detection method based on deep learning. The pedestrian mask wearing real-time detection method comprises the following steps: S1, establishing a robust backbone network; S2, carrying out the multi-scale training; S3, performing model compression; S4, performing model optimization. According to the method provided by the invention, more labor overhead cost, and calculation cost and time overhead cost of the small hardware storage device are considered. Whether a pedestrian wears the mask or not can be judged more quickly, and good engineering practicability is achieved.

The invention relates to a method for measuring a steel strut axial force by utilizing an adhered steel sheet, and the method comprises the following steps: (1) designing a standard steel sheet and marking the optimal tensioning state frequency f and standard calculating coefficient K of the standard steel sheet; (2) choosing the required adhered steel sheet according to the marking result, installing the chosen adhered steel sheet on a steel strut at an unstressed state before installing the steel strut, then adjusting the adhered steel sheet to the optimal tensioning state, and recording the calculating coefficient K of the adhered steel sheet at the optimal tensioning state; and (3) bearing an axial pressure by the steel strut in the use process of the steel strut, measuring the frequency value fi of the adhered steel sheet at such a state, and according to an axial force formula shown in the specification, calculating and acquiring the axial force F of the steel strut, wherein E represents a steel strut elastic modulus and A represents a cross sectional area of the steel strut.

The invention discloses a three-dimensional fine modeling method for an immersed tube tunnel. The method comprises the following steps of: performing structural analysis on the immersed tube tunnel to determine the part needing modeling; defining a node on the axis of the immersed tube tunnel model; defining a unit required by the immersed tube tunnel model; defining material properties and interface attributes; defining the constraint relationship between the node simulating the joint part and the endpoint of the tube section; and assembling the components into an immersed tube tunnel model for calculation and analysis. The method disclosed by the invention can simulate the joint initial compression produced by water-power compression joint in the construction of the immersed tube tunnel, accurately calculates the stress and opening amount of the joint, and realizes the fine calculation of the joint part. The method disclosed by the invention sufficiently considers the requirement of analysis accuracy, meets the requirement on the calculation efficiency, and has good engineering practicability.

The invention belongs to the technical field of satellite communication antennas, and particularly relates to a VICTS antenna four-point tracking algorithm, which comprises the following steps: firstly, carrying out directional diagram testing on a VICTS antenna to obtain an antenna far-field directional diagram of which the beam center is changed according to a pitch angle; Performing beam modeling according to the antenna far-field directional diagram; And finally, solving a difference value of the collected four-point level, and solving an azimuth angle difference value and a pitch angle difference value of the target direction relative to the initial beam center by utilizing beam modeling. According to the invention, target tracking can be carried out on the satellite of which the beamcenter is at any pitch angle and the angle difference between the target position and the beam center is less than 2 degrees, and the tracking precision and tracking efficiency of the VICTS antenna are improved.

The invention discloses a pipeline defect intelligent detection method based on image processing and deep learning, and application thereof. The intelligent detection method comprises the following steps: carrying out preprocessing including edge detection on pipeline image data, inputting the preprocessed image into a trained detection model, and carrying out defect detection, wherein the detection model is constructed based on a Darknet53 backbone network and a multi-scale feature extraction network. According to the detection method, different defects of the pipeline can be accurately recognized and detected, the model meeting the industrial application level is obtained, the detection efficiency is high, and the environment universality is high.

The invention provides a friction damper capable of achieving variable damping force output, and belongs to the technical field of damping devices. The damper comprises sliding plates, friction plates, fixed plates, a core plate, a butterfly spring, pre-tightening nuts and pre-tightening bolts. The fixed plates, the sliding plates and the friction plates are all used in pairs, and are symmetrically mounted through the pre-tightening nuts and the pre-tightening bolts. The damper can generate certain damping force under the action of the pretightening force of the bolts; when the damper bears anexternal load, straight sections of the sliding plates make contact with straight sections of the fixed plates in advance and slide, and at the moment, the contact surfaces of the sliding plates andthe friction plates achieve friction energy consumption under the action of constant pressure. The characteristic that the damper outputs variable damping force along with the change of the external load can be achieved, and the damper can adapt to seismic loads under different intensities. The damper has the advantages of being symmetrical in structure, easy to install, convenient to use and capable of bearing offset loads, and the structure has a stroke limiting function.

The invention discloses a collision-proof and vehicle fall-proof device of a bridge and capable of buffering impact. The device comprises a bridge concrete pavement layer and an overhang bearing plate. The bridge concrete pavement layer is provided with a sandwich layer, which is used for receiving the overhang bearing plate; two sliding layers are arranged in the bridge concrete pavement layer, and the overhang bearing plate is arranged between the two sliding layers, so that the overhang bearing plate can freely slide in the bridge concrete pavement layer; the outer end of the bridge concrete pavement layer is provided with an anti-dropping blocking part, and the rear end of the overhang bearing plate is provided with a blocking part, so that the anti-dropping blocking part can form blocking of the overhang bearing plate and prevent the overhang bearing plate from being separated from the bridge concrete pavement layer in the process of outward movement; a buffering device is arranged on the inner side of the anti-dropping blocking part, when the vehicle strikes a guardrail, the buffering device is struck by the blocking part of the overhang bearing plate, and under the action ofthe buffering device, a strong impact force is relieved and released, thereby playing a buffering role on the vehicle and ensuring the safety of the vehicle.

The invention provides a testing device and a testing method for dynamic characteristics of joint curved surface faying surfaces. The testing device comprises an excitation system, a loading system, a test bench system and a signal acquisition, analysis and processing system, wherein the excitation system consists of a vibration exciter, an exciter hanging beam and a bracket; the loading system consists of a loading bolt A, a loading spring A, a loading bolt B, a loading spring B, a loading bolt C, a loading spring C, a loading bolt D and a loading spring D; the test bench system comprises a pedestal, a lower bridge plate, a block to be tested and an upper bridge plate; and a computer in the signal acquisition, analysis and processing system sends out a known excitation signal to make the vibration exciter excite vibration, acquires a response signal in the system for calculation, and obtains dynamic characteristics of the joint curved surface faying surfaces. The testing device and the testing method can achieve the purpose of measuring dynamic characteristics of joint curved surface faying surfaces of various kinds of different materials, and have the advantages of good interchangeability, simple operation and reliable data.

The invention discloses a turbine blade nonlinearity creep analysis method based on beam theory. The method comprises the following steps: a, a material creep parameter of a turbine blade under a plurality of temperature within scope of work is determined; b, working time is divided into a plurality of time steps; c, a plurality of section of turbine blade is selected, and a divided gridding is divided; d, a stress and durable damage of blade based on beam theory in each time step after creeping and creeping deformation is obtained; e, a turbine blade creep deformation extension and a creep deformation durable damage are obtained. The main element of the turbine blade creep deformation is considered, and is convenient and fast, the engineering practical demand can be met, obtained efficiency is increased hundreds of times, the projects blade contrastive analysis, the full-life blade creep analysis and the turbine blade on line lifetime monitoring are suitable, the engineering practicability is better. The creep deformation prolongation and the creep rupture life for polytopes launch turbine blade are analyzed and verified, the long-term- test effect of engine is indicated, obtained data precision can be met for engineering practical requirement.

The invention relates to the technical field of distribution network optimization, in particular to a low-voltage transformer area low-voltage risk assessment method based on distribution network loadprediction, which comprises the following steps: acquiring monthly maximum load and previous monthly growth rate of each transformer area, and predicting monthly maximum load of each transformer areain the current monthly; acquiring monthly newly installed capacity, and estimating the load growth amount caused by the reported capacity according to the former newly installed capacity coincidencerate; carrying out superposition prediction on the actual monthly maximum load of the low-voltage transformer area; calculating a voltage drop amplitude by taking the actual monthly maximum load as aline end load, and preliminarily evaluating a low-voltage transformer area of an emergency risk; for the voltage drop proportion caused by the newly-added 10 kW installed capacity, a low-voltage transformer area with great and general risks is evaluated. According to the method, the voltage states of the head end and the tail end are considered, the influence of the installed capacity is brought into the work of load prediction and low-voltage risk assessment, the assessment process is simple, implementation is convenient, the engineering practicability is good, and the low-voltage risk statecan be tracked regularly and comprehensively.

The invention belongs to the technical field of damping energy dissipation devices, and particularly relates to a self-adaptive variable friction damping device suitable for the seismic environment and a self-adaptive variable friction damping method. The friction damping device is used for resisting seismic loads in an earthquake. The friction damping device comprises a first sliding plate, a second sliding plate, a first fixing plate, a second fixing plate, a first main friction plate, a second main friction plate and a core plate. The first fixing plate, the first sliding plate, the core plate, the second sliding plate and the second fixing plate are stacked. The first main friction plate and the second main friction plate are symmetrically embedded in the upper and lower faces of the core plate. According to the self-adaptive variable friction damping device, the reverse discontinuous slope surface structure design is adopted, the force is more uniform and stable when the fixing plates and slope plates interact in the inclined planes through the force layout mode of the triangular position slope surfaces, the output of the variable damping force during pulling and pressing bidirectional movement can be easily achieved, the double-stroke limiting function can be realized by means of a self-concave-convex structure, and good engineering practicability is achieved.