115results about How to "Add constraints" patented technology

Disclosed are a model prediction control method and a model prediction control system for all working conditions of a wind generating set. The system comprises an MPC (model prediction control) device, a feedback information measurer, a wind wheel, a driving chain, a tower, a generating unit, a variable propeller driver and a converter. The feedback information measurer is used for detecting status variables of the wind wheel, the driving chain, the tower and the generating unit and transmitting detecting results to the MPC device, the MPC device is used for computing targets of the blade pitch angle and the generator torque, and the variable propeller driver and the converter are used for adjusting the blade pitch angle and the wind generator torque. The method is used for computing control increment by means of a variable propeller control prediction model and a torque control prediction model, takes the status variables including driving chain torsional displacement, driving chain torsional speed, blade plane external first-order flap displacement, blade plane external first-order flap speed, tower front-back first-order swing displacement, tower front-back first-order swing speed, mechanical loads of the unit and the like, and two prediction models can be automatically switched in different working conditions, so that the wind generating set can be operated in all working conditions.

The invention relates to a method of constructing a fine discrete road grid in an urban drainage simulation system and belongs to the cross field of municipal engineering information technology, database technology and geologic information system technology. From the demand on construction of a waterlogging simulation model, under the restraint conditions in road design specifications and on the basis of conventional map measured elevation points, the number and positions of interpolation points are optimized under the drainage simulation system platform by the fitting method of local elevation change curves of cross-longitudinal road section and by road characteristic terrain vector layers according to mathematical model interpolation encryption plane and elevation information of physical road tomography; accordingly, a fine discrete road elevation grid unit is constructed, true tomographic road features are expressed quickly and economically, the demand on precise simulation of waterlogging models is met, especially the dredging and resisting actions of road micro-tomographic features upon waterflow can be correctly expressed, and the method is significant to promotion and application of the drainage simulation technology.

The invention discloses a control method for ordered charging of an electromobile. The control method comprises the following steps of firstly, establishing a charging load characteristic model of the electromobile by integrating factors of battery characteristics, a charging mode and behaviors and habits of users; secondly, with the goal of minimizing the difference between the peak and the valley of a load, establishing a centralized optimization model according to the minimal variance of load demands at all time intervals and the average load level, enabling the load fluctuation to be minimized, and realizing the stabilization of the load to obtain reference optimized power; thirdly, establishing a distributed optimization model, and optimizing an individual charging scheme according to the reference optimized power obtained by a power grid and a middle manager in the optimizing process of the second step and dynamic electricity price in 24 hours. A cooperative control model is established by adopting a centralized and distributed combined optimized control idea, so that the negative effect of large-scale disordered charging of the electromobile on planning and operation of the power grid is reduced.

The invention discloses an optical calibration method of an ultrasonic probe. The optical calibration method of the ultrasonic probe includes the following steps: (1) pasting character identification points on the ultrasonic probe, (2) fixing a three-dimensional calibration template and optical positioning equipment, (3) and holding the ultrasonic probe in hand to scan the three-dimensional calibration template, obtaining a space gesture of the ultrasonic probe by using the optical positioning equipment at the time of every time gathering ultrasound images to obtain original data and calibrating the ultrasonic probe by using a least square method. Compared with a traditional electromagnetic calibration method, the optical calibration method of the ultrasonic probe has the advantages that calibration results are more accurate, due to the fact that in the process of calculation only an unknown number exists (an unknown transformation matrix), complexity of calibration calculation is reduced, the optical calibration method of the ultrasonic probe can be applied into various types of ultrasound probes, equipment is simple and convenient and range of application is wide. The optical positioning equipment is used for obtaining the gesture of the ultrasonic probe, influence of power cords is not needed to consider and calibration range is wider, and the optical positioning equipment does not have a problem of electromagnetic compatibility in a surgical navigation environment.

The invention discloses a multi-target dynamic scheduling method for a wind storage hydrothermal power system based on multi-source complementation, and the method comprises the following steps: 1, building a multi-target dynamic economical scheduling model: 1.1, building four optimization targets: take the minimum thermal power coal consumption, the minimum thermal power output adjustment volume, the maximum thermal power generation and the minimum load fluctuation after the thermal power is inputted to a power grid; 1.2, determining the constraint conditions of the four optimization targets; 2, carrying out the weighting and conversion of the four optimization targets, and obtaining a target function F of the multi-target dynamic economical scheduling model; 3, combining with the target function F, and solving the multi-target dynamic economical scheduling model through employing the improved plant growth simulation algorithm. According to the invention, the method gives full consideration to the economical performance and stability of thermal power operation, the utilization rate of the wind power and hydropower and the adjustment effect of a pumped storage power station, and guarantees the economical performance and stability of operation of the thermal power generating unit while promoting the consumption of the wind power.

The invention discloses an optimization method of cycloid pin wheel profile modification based on particle swarm algorithm, and the method comprises the steps of determining a design variable and an object function according to a basic parameter of a cycloid wheel; re-determining a constrained condition according to a traditional constraint method and constraint requirements to a reshaped cycloid wheel tooth tip gap and a tooth root gap provided by the invention; playing the global optimization ability of particle swarm optimization algorithm in combination with the reshaped characteristics of the cycloid wheel to construct a particle swarm optimization algorithm model after the cycloid wheel shaping optimization; making an optimization object that the reshaped tooth profile can get close to a corner shaping tooth profile maximally and a return difference as small as possible is guaranteed, and further increasing the constraint requirement to the tooth tip gap and the tooth root gap on the basis of the traditional constraint, thereby obtaining a shaping tooth profile with an optimal equidistant and offset. In this way, the invention discloses the optimization method of cycloid needle wheel tooth profile modification based on the particle swarm algorithm with a short calculating period and high calculating precision, and the effect is good.

The invention discloses a compound nanofiber lithium battery diaphragm and a preparation method thereof. The compound nanofiber lithium battery diaphragm is characterized in that the compound nanofiber lithium battery diaphragm structurally comprises an upper layer nanofiber diaphragm layer, a middle layer nanocellulose gel layer and a lower layer nanofiber diaphragm layer, and the compound battery diaphragm containing the three-layer structure is prepared by utilizing an electrostatic spinning method and a sol-gel combination method. The preparation method of the compound nanofiber lithium battery diaphragm comprises the following steps: step (1), preparing nanocellulose suspension liquid; step (2), preparing a polymer electrostatic spinning solution; step (3), performing electrostatic spinning; step (4), enabling the lower layer nanofiber diaphragm layer prepared in the step (3) to be infiltrated by acid liquor of which the pH is 3 to 6; step (5), preparing the middle layer nanocellulose gel layer; step (6), preparing the upper layer nanofiber diaphragm layer. The prepared three-layer-structure compound nanofiber lithium battery diaphragm final product is the compound battery diaphragm.

The invention discloses a method for intelligently identifying mineral information based on spectral information. The method comprises the following steps of: (1) extracting the spectral information comprising spectral waveform and spectral characteristic parameters; (2) reading in hyperspectral image data; (3) resampling each reference spectrum according to the wavelength of the image spectrum; (4) removing continuum of the image spectrum and the resampled reference spectrum; (5) performing least square fitting on the image spectrum and each reference spectrum processed by the step (4) at a primary absorption characteristic band and a secondary absorption characteristic band to obtain an initial matching value; (6) performing three kinds of constraint processing, namely matching of spectral angle at a characteristic band, judging of existence of specific absorption characteristic and setting of a reflectivity threshold value of the characteristic band, on the initial matching value to obtain the final matching value; and (7) obtaining the final identification result of the hyperspectral image by using the constraint of spatial distribution continuity of a mineral, wherein the reference spectrum corresponding to the maximum matching value in the final matching values obtained by the step (6) is a preliminary identification result of a pixel.

The invention discloses an orthogonal plane calibrating method and an orthogonal plane calibrating system of relation between a laser distance measuring device and an end of a mechanical arm. The laser distance measuring device is fixedly disposed on the end of the mechanical arm, and the calibrating planes, which are orthogonal to each other, are disposed in the space. Under the driving of the rotating translational motion of the mechanical arm, the posture of the laser distance measuring device can be changed, and the distance d measured by the laser distance measuring device can be used to solve the translational vector r and the unit direction vector v of the laser beam, and the calibrating of the space transformation relation between the laser distance measuring device and the end of the mechanical arm can be completed. The reconstruction of the point x of the object in the three-dimensional object can be realized according to the x=r+dv. The transformation relation between the coordinate system of the end of the mechanical arm and the coordinate system of the laser distance measuring device can be determined clearly. By using the calibrating plane as the orthogonal plane and adopting the non-linear optimization method, the coplanarity of the points can be fully used as the constraint condition to solve the calibrating problem of the space transformation relation, and therefore the constraint condition can be added, the errors can be reduced, the noise interference can be reduced, the robustness and the easy implementation of the method can be improved, and the calibrating precision of the space transformation relation can be improved.

The invention discloses a non-linear constrained least square-based single station positioning method. The method comprises the steps of first, building an NLOS signal transmission model of a macro cell single base station according to a signal transmission characteristic of a macro cell; then, converting a positioning problem into a non-linear constraint least square problem by using a position relationship among a multi-path signal parameter, a base station, a target and a scatterer; resolving the least square problem by using an LM (Levenberg-Marquardt) algorithm; and when a residual is large, introducing an aquasi-Newton algorithm, and improving the LM algorithm so as to obtain a target estimation position. The method solves a problem that a traditional positioning algorithm depends on the number of base stations, performs positioning by using a single base station, does not need clock synchronization, and lowers the algorithm complexity; in the NLOS environment, the multi-path signal is used as a positioning path but does not suppress multiple paths, so that a problem of large positioning error in the NLOS environment is solved; the variable constraints are increased by using a ring model, so that the least square method is more effective, and the single station positioning of the macro cell reaches the positioning accuracy of 20-30 meters.

The invention discloses a bidirectional green wave coordination control method based on red lamp queue clearance constraint condition in an improved MAXBAND model. The method comprises the following steps of determining a single-point timing scheme of each intersection in trunk coordination; determining a common period of a coordinated road segment; correcting a constraint condition in a traditional MAXBAND model, wherein the step comprises correcting a green conflict constraint condition and an integral-time period constraint condition, and adding a head vehicle constraint condition and a determining screening condition; and through correction in a previous step, finally subdividing a MAXBAND model into two models, namely a model A and a model B, and solving by means of the improved MAXBAND model algorithm. According to the bidirectional green wave coordination control method, through performing geometric meaning correction on the red lamp queue clearance time in the traditional MAXBAND model, the determining screening condition of the algorithm model and the constraint condition of head vehicle mode are added, and a green wave coordination problem in actual engineering can be more accurately described and settled, thereby realizing an effect of improving optimal controlling in trunk bidirectional coordination.

The invention relates to a multi-heat-source heat supply system load scheduling distribution method and system based on urban atmospheric diffusion process simulation prediction. The method comprisesthe following steps that S1, all heat source pollutant emission models are established; s2, establishing a heat supply network model, a heat source side load constraint, a heat supply network transmission and distribution capability constraint and a heat supply network splitting model, and determining a multi-heat-source load distribution feasible region; s3, importing the multi-layer regional simulation meteorological data and the pollutant list as boundary conditions into an atmospheric quality prediction model system, generating pollutant concentration space-time distribution, and verifyingthe model; s4, establishing an atmospheric quality evaluation system; and S5, constructing a target function of the lowest atmospheric pollution, and performing multi-scheme comparison on line to ensure that the atmospheric quality of the key region reaches the standard in a specific period and obtain an optimal multi-heat-source heat supply system load scheduling distribution scheme. The methodand the system provided by the invention can effectively solve the problem of air quality guarantee during major activities.

The invention aims at providing a multitemporal remote sensing image-based subpixel positioning method, which comprises the following steps of: inputting a remote sensing image with low resolution, obtaining various component diagrams of the remote sensing image through a spectral unmixing technology, and obtaining an initial space distribution of subpixels by using an SPSAM (Sub-Pixel Spatial Attraction Model) method according to component diagrams; selecting pixels Pab to be analyzed from the remote sensing image with low resolution, calculating an energy function Uc,ij of a Pij when the Pij belongs to each category c, finding out the category corresponding to a minimal Uc,ij, and judging that the Pij belongs the category; carrying out the above operations on each subpixel Pij in the Pab; carrying out the above operations on each mixed pixel to be analyzed in the remote sensing image with low resolution; and repeating the above steps until the difference of the number of different pixels of a front output subpixel positioned image and a rear output subpixel positioned image is less than 1%. The method provided by the invention has higher accuracy for positioning the subpixels, and the SPSAM is adopted for initializing, so that uncertainty resulting from random initialization does not exist in the output positioning result.

The invention relates to a demand response-based intelligent control method for a home energy management system. The method comprises the following steps that initial parameters are input, and a population is randomly generated by an initialization operator; a target function for spending the least electricity fee is built, constraint conditions are set, and a fitness model is constructed; the fitness model is solved to obtain the equipment states in all the scheduling time periods, and storage battery charging and discharging are conducted according to the equipment states in the scheduling time periods; a selection operation and a crossover operation are conducted in sequence, whether the population meets the constraint conditions or not is judged, and if not, variation is conducted after population repairing; if yes, variation is directly conducted; and whether the population obtained after variation meets the constraint conditions or not is judged, and if not, population repairing is conducted. Compared with the prior art, the method has the advantages of adopting peak-load shifting to transfer part of the distributed energy generating capacity, being more flexible in application, adopting the repairing method to meet the constraint conditions, being more suitable for some complex non-linear integer model problems and the like.

The invention belongs to the technical field of multichannel clutter suppression, and particularly relates to a multichannel clutter suppression method based on robust principal component analysis. The multichannel clutter suppression method based on the robust principal component analysis comprises the following steps of obtaining a distance-Doppler image corresponding to each reception channel of radar; obtaining corresponding distance-Doppler data according to each distance-Doppler image; conducting column vectorization on distance-Doppler data matrices, and combining all column vectors into a matrix X; decomposing the matrix X through the robust principal component analysis so as to obtain a corresponding sparse matrix S0; according to the sparse matrix S0, obtaining 1 to m, wherein 1 to m are submatrices of X1 to Xm; according to 1 to m, obtaining the optimal weight wopt,j corresponding to a jth Doppler unit; conducting clutter suppression according to the optimal weight corresponding to each Doppler unit, and obtaining a result Xout after clutter suppression.

The invention provides a STATCOM (Static Compensator) device based on a switched system theory. The STATCOM device comprises a reactor L, a voltage type inverter, a driving circuit, an outer ring control module and an inner ring control module. A control method for the STATCOM device comprises the following steps of modeling, signal acquisition, synchronous compensation, stability verification and feedback control. The control method has the following advantages that: (1) when a system is in failure, the stability of the system can be ensured, and interferences on performances of the system can be eliminated; (2) a confirmed voltage output function can reduce parameters which are taken into consideration in operation, and only parameters of resistance and inductance are required; (3) optimized indexes can be confirmed through a determined robust control model according to the definition of H (infinite) control of the control method; (4) the utilization of constraint conditions of an LMI (Linear Matrix Inequality) solving controller is the most convenient; and (5) the effectiveness and correctness of STATCOM compensation can be achieved by reasonably switching a turnoff device in a main circuit of the inverter based on switching rules, the utilization rate of the device is increased, and the service life of the device is prolonged.

The embodiment of the invention discloses a positioning method and device, which are used for reducing the number of sending stations so as to reduce the calculation complexity of positioning. The method provided by the embodiment of the invention comprises the following steps: a terminal receives positioning auxiliary information sent by a positioning entity, wherein the positioning auxiliary information comprises a cell identifier of a cell where a to-be-measured sending station is located, an identity identifier of the to-be-measured sending station and positioning reference signal configuration information of the to-be-measured sending station; the terminal measures the to-be-measured sending station according to the positioning auxiliary information to obtain a measurement result, andthe measurement result comprises measured positioning reference signal information of the to-be-measured sending station; and the terminal sends the measurement result.

The invention discloses an image and text retrieval method based on graph neural network structure modeling, and the method comprises the steps: employing an attention mechanism to represent the fine-grained vision extracted from a picture and a text, and enabling text elements to calculate the similarity of the picture and the text better; a graph structure is constructed in a self-adaptive modethrough visual and text elements, features are updated through a graph convolution method, and the intra-modal and inter-modal relation of the visual and text elements can be better considered; a constraint mechanism is introduced between different pictures and text pairs and in the visual and text element alignment process, fine-grained text elements can correspond to corresponding picture areaseasily, then the reliability of picture and text level similarity calculation is improved, and the accuracy of picture and text retrieval is improved.

The present invention relates to a multi-component seismic data Corssline direction wavefield reconstruction method based on Shearlet transform, which attributes the seismic data reconstruction to l1 regularization based on Shearlet sparse constraints; utilizes the simultaneous observation of pressure and acceleration in multi-component measurement, and the gradient is The reconstructed seismic data provides additional information, which can reconstruct the data more accurately; the P and acceleration wavefields are reconstructed in an alternate iterative manner. The fundamental difference between this method and other methods is that it expands to multi-component seismic data interpolation on the basis of single-component seismic data interpolation. Since the addition of velocity components increases constraints, better reconstruction results can be achieved. It solves the problem that the existing single-component seismic Crossline direction seismic wavefield reconstruction method has low precision, cannot effectively reconstruct small underground structures, and is difficult to reconstruct. Solved the problem that the reconstruction effect of Curvelet with large curvature is not good. The cost is reduced and the accuracy is improved.

The invention provides a seismic data velocity model establishing method and device. The method includes the following steps that: the objective function of a seismic data velocity model is determined; the gradient of the objective function is calculated based on horizon constraint; and the objective function is adjusted according to the calculated gradient, so that a post-adjustment velocity model can be obtained. According to the method provided by the embodiment of the invention, the horizon constraint is introduced in the computation of the gradient of the objective function, namely, constraint conditions are added, and therefore, the problem of multiplicity of solution in a wave equation-based modeling method in the prior art can be solved; and the gradient is determined based on the introduction of the horizon constraint, so that the finally-determined velocity model can contain horizon information, and thus, the obtained velocity model more accords with a geological structure.

The invention discloses a variety selection method and a variety selection device based on a neural network algorithm and the portfolio theory. The method comprises the following steps: predicting the yield of each variety in available varieties when each variety is separately planted in a preset area under different natural conditions through a yield prediction model built based on a neural network algorithm; acquiring the constraint parameter values for the planting of the available varieties in the preset area, wherein the constraint parameter values include at least one of the following: the upper limit of the number of varieties planted in the preset area, the upper limit of proportion of each variety planted in the preset area, and the lower limit of proportion of each variety planted in the preset area; and determining the values of combined parameters of varieties planted in the preset area through an objective function, wherein the objective function is determined based on the portfolio theory, and the objective function is used to at least increase the expected yield of the preset area or at least reduce the yield variance of the preset area. The technical problem that the variety selection method in the related technology is not realistic enough is solved.

The invention discloses a topological optimization design method on the basis of pseudo-density sequencing and with consideration of draft manufacturing constraints, which is used for realizing introducing draft manufacturing constraints in a topological optimization design of an irregular grid model. The technical scheme includes that the topological optimization design method includes sequencing the pseudo-densities of units on the same row in a draft direction again by the aid of a unit pseudo-density sequencing method; leading the pseudo-densities of the units to be distributed from large to small in the draft direction; and accordingly realizing draft constraint. By the aid of the method, design requirements of the draft constraints can be met without introducing a large quantity of constraints. The topological optimization design method solves the problems that a large quantity of constraint conditions are introduced into an existing method and a topological optimization process is not converged due to the excessive constraint conditions.

The invention relates to a special A-type frame air spring rear suspension for a large coach, comprising an A-type frame; the front end of the A-type frame is connected with a link assembly; the two sides of the rear end of the A-type frame are sequentially provided with an air spring assembly and an absorber; the A-type frame is provided with a flexible connection end bracket of a height control valve; the rear end of the A-type frame is connected with a transverse stabilizer bar. The invention has simple structure, light weight, little peculiar parts, multiple general parts and low cost; and the rear suspension is easy to manufacture, and the axle location is accurate and reliable without regulation.

The invention belongs to the technical field of electrical power system interval power flow calculation, and particularly relates to an improved method of a power grid interval power flow consideringinterval correlation. The improved method includes the steps that electrical power system parameters are input; an affine algorithm is used for transforming the interval power flow into a nonlinear optimization problem; output variables X and X<j> of the nth pair generator with correlation is selected; a parallelogram model among related variables is established; the parallelogram model is converted into inequality constraint conditions in the analytical form; n=n+1, the conditions that if n>=N, the next step is executed; and if not, the previous step is returned are judged; and power flowequation constraints and correlation constraints are simultaneous, and a nonlinear optimization algorithm is used for solving the interval flow. According to the improved method of the power grid interval power flow considering interval correlation, correlation between the variables in an electrical power system is considered, uncertain power flow calculation is more accurate, and more accurate reference is provided for electrical power system scheduling.

The invention discloses a low-energy-consumption posture analysis method under the standing state based on a bionic foot robot. The research is performed for the relation between the posture and the energy consumption of the foot robot, firstly the output torque of each joint of the legs is obtained through static leg analysis and the overall energy consumption model of the foot robot is established; then the motion flexibility of the robot is comprehensively considered, the maximum step performance indicator is introduced and the multi-objective function based on the energy consumption and the maximum step is established; and the low-energy-consumption posture of the robot is obtained through MATLAB simulation. The reliability and the effectiveness of the analytical method are proved by the experiment, the objectives of reducing energy consumption and increasing work endurance time can be achieved by adjusting the posture of the robot under the horizontal environment by establishing the dynamic relation between the robot posture change and the energy consumption and thus the method has important meaning for the static posture research of the robot.

The invention discloses an electromagnetic thrust bearing structural parameter optimization method based on a double-target genetic algorithm. According to the method, under the premise that it is ensured that an electromagnetic thrust bearing serves as a high-speed bearing to obtain excellent dynamic characteristics, coil energy loss and the bearing quality are used as optimization targets, constraint function relationships among the bearing capacity, the magnetic flux density, temperature rising, a magnetic circuit and the like are built, multi-target optimization is transformed into single-target optimization by utilizing a linear weighting method, global optimization is conducted on structural parameters of the electromagnetic thrust bearing in a solution space of a comprehensive optimization target function by adopting the genetic algorithm, the local optimal point can be skipped over to achieve the effect of global convergence, non-dominated solutions of two targets are obtained,the deficiencies of a direct method and an indirect method are made up to a certain degree, the dynamic characteristics of the electromagnetic thrust bearing are effectively improved, and resources and the time are saved; and high-precision structural parameter design of the electromagnetic thrust bearing is achieved.

The invention discloses a parallel binocular camera calibration method based on three-dimensional reconstruction, and the method comprises the steps: carrying out the multi-azimuth and multi-angle photographing of a calibration plate through a binocular camera, and obtaining a plurality of groups of left and right images of the calibration plate; obtaining camera initial parameters by using a Zhang Zhengyou calibration method; introducing a centroid increment formula, eliminating the influence of a coupling effect between a rotation matrix and a translation vector in a parameter updating process, constructing a cost function, and avoiding an overfitting phenomenon in a rotation matrix calculation process by utilizing least square method regularization; constructing a cost function betweenthe theoretical three-dimensional coordinates of the feature points and the true values of the corresponding feature points in a world coordinate system, and meanwhile, utilizing epipolar constraint and epipolar distance constraint to improve the convergence of the cost function and improve the accuracy of updating camera parameters.

The invention relates to a composite front suspension special for a large coach, comprising a guide leaf spring; the guide leaf spring is respectively provided with an air spring sac and a bracket, a damper and a lateral stability torsion bar. The invention maintains the original good performance of the air spring, thereby overcoming the acute shortcomings of the air spring front suspension guided by multiple connecting bars; and the invention has simple structure, accurate front axle positioning, safety and reliability, light self-weight and low cost.

The invention discloses an orthodontic arch wire variable radius circular domain division method based on bending point angular distance ratio sum, relates to the technical field of orthodontic arch wire bending. Aiming at an orthodontic arch wire curve with relatively small bending point density, based on an orthodontic arch wire curve bending point information set and a robot bending informationset of bending points, and in combination of the motion characteristics of a robot bending orthodontic arch wire, the orthodontic arch wire variable radius circular domain division method based on the bending point angular distance ratio sum is established. The method is technically characterized by comprising the following steps of converting an orthodontic arch wire curve T into a plane curve T'; performing setting and simplifying on circular domain limiting parameters; determining the radius and the circle center of the divided circular domain; defining a bending circular domain with a reasonable angular distance ratio; judging whether circular domain division is continued or not; and by taking the angular distance ratio of the bending points of the circular domain as an index, arranging the circular domains in a descending order, specifying the bending point sequence of the circular domains, and outputting the final bending point bending sequence T1 and R1. According to the method, the variable radius circular domain is used for dividing, the angular distance ratio sum of the bending points is used as a judgment condition, the orthodontic arch wire bending planning efficiencycan be improved, and the problem of interference in the orthodontic arch wire bending process of a robot is avoided.

The invention discloses a double-pre-film type ultrasonic spray nozzle, specially an ultrasonic atomizing spray nozzle suitable for a combustor, which belongs to the field of industrial combustion. The double-pre-film type ultrasonic spray nozzle comprises a spray tube, a central rod, a resonant cavity, a flat gasket and a hexagonal nut, wherein the outlet section of the spray tube is equipped with a convergent spray tube; the inner part at the left end of the central rod is hollow; the right end of the central rod is equipped with a solid rod; the outer surface of the solid rod is tapped withthreads; and the resonant cavity, the flat gasket and the hexagonal nut are connected by the central rod. Double-pre-film type oil spray and convergent spray tube type design are adopted, so that thespray nozzle can realize secondary atomizing; fuel oil flow and air flow can be met according to the dimension of a to-be-regulated structure; and meanwhile, a distance from the resonant cavity to anoutlet of the spray tube can be regulated to obtain different spray angles. The double-pre-film type ultrasonic spray nozzle is simple in structure, is small in gas-liquid ratio, is good in atomizingeffect, is great in atomizing angle variable range, sufficiently utilizes structure characteristics, flow field characteristics and sound pressure characteristics of an ultrasonic generator, greatlyimproves atomizing quality of fuel oil from structure and principle, and improves combustion efficiency.