40results about How to "Reliable design" patented technology

The invention provides a method and device for optimizing the design of a hybrid power system of an aircraft. The method provided by the invention comprises the following steps: aiming at a pre-designed hybrid power system, constructing a simulation model corresponding to the hybrid power system; determining a required power range of a power system according to the flight envelope of the aircraft, and determining load required power of the aircraft under multiple types of preset typical working conditions according to the required power range; determining a working mode of the aircraft under the load demand power according to the load demand power under each type of preset typical working conditions and current and preset working mode determination rules; simulating the working mode by using the simulation model, and obtaining a simulation result; wherein the simulation result comprises operation parameters corresponding to each model; and according to a simulation result, providing an optimization suggestion for a pre-designed aircraft hybrid power system. The method provided by the invention is used for effectively optimizing the design of the hybrid power system of the aircraft and improving the performance and reliability of the hybrid power system.

The invention discloses a recovery positioning measurement system based on joint positioning of dynamic-dynamic difference and optical measurement, and the system comprises a Beidou differential positioning device which carries out the self-positioning measurement based on a Beidou global navigation system in real time through a navigation antenna, and outputs an absolute positioning result of a rocket system; pseudo-range differential and carrier phase differential relative positioning is carried out through Beidou satellite reference information collected by a differential antenna and dynamic reference recovery platform self-positioning information sent by a rocket system, and a satellite relative positioning result is obtained; the optical fusion system is used for acquiring optical beacon information and outputting an optical relative positioning result; the data comprehensive equipment outputs a comprehensive relative positioning result to the rocket system; the rocket system receives and demodulates the information sent by the ground data transmission equipment through the data transmission equipment and the data transmission antenna, and analyzes the self-positioning information of the dynamic reference recovery platform; and performing rocket control according to the absolute positioning result and the comprehensive relative positioning result. According to the invention, the positioning precision is improved.

The invention belongs to the technical field of flight training platforms, and provides a flight skill enhancement training supporting platform fusing virtual imaging and motion capture, the flight skill enhancement training supporting platform comprises a real object cabin and a virtual device, the real object cabin provides a cabin real object part for airplane training and comprises a cabin body, a flight seat and a control component, the virtual device is arranged in the cabin body, and the flight seat is arranged in the cabin body. And providing a virtual cabin based on a virtual scene for the flight trainee, wherein the virtual cabin comprises a simulation flight picture and a cabin scene of a non-cabin real object part. The system is integrally designed on the basis of a virtual-real combination technology, an XR video straight-through acquisition motion capture technology and a commercial shelf product building platform mode, the technology is safe and reliable, implementation is convenient and feasible, and use and maintenance guarantee are simple and convenient. By constructing a platform comprising an XR head-mounted display and a computer component, flight skill enhanced training fusing virtual imaging and motion capture is realized. Verification shows that the design is reliable and effective, and has great significance for realizing flight skill enhancement training with low cost and high interactivity combined with virtuality and reality.

The invention discloses an MEMS sensor intelligent design method and system oriented to a universal design scene. The method comprises the steps that a large number of structural parameter-performance parameter data pairs of MEMS sensors are obtained based on finite element simulation; constructing and training a verification network to establish a mapping relation from structure parameters to performance parameters; the fuzzy range, the accurate numerical value and the unconstrained three different design demands are converted into unified interval representation, and a reverse generation strategy is used to construct a data set containing the design demands; constructing and training a search network to realize a mapping relation from a design demand to a feasible structure; and a precision optimizer is constructed to improve the quality of a feasible solution output by the search network. Compared with a traditional intelligent design model, the model expansibility is high, multiple design requirement types can be supported without retraining, the capability of automatically iterating and optimizing precision is achieved, and therefore high-precision and rapid MEMS sensor design is achieved.

The invention provides a design method and device for a buckling-restrained brace for reinforcing a concrete frame structure, and relates to the technical field of building design. The design method for the buckling-restrained brace for reinforcing the concrete frame structure comprises the steps that a concrete frame structure design drawing of a target building is obtained; according to the concrete frame structure design drawing, the position information of the first buckling-restrained brace capable of being arranged of the target building is obtained through the buckling-restrained brace position prediction model; wherein the anti-buckling support position prediction model is a machine learning model obtained by training a training data set; and according to the position information of the first buckling-restrained brace capable of being arranged, the buckling-restrained brace design of the target building is determined. According to the method, the buckling-restrained brace design for reinforcing the concrete frame structure can be efficiently and reliably completed.

This invention relates to the field of prefabricated structure technology for energy storage power stations, specifically to a prefabricated foundation structure for an energy storage power station equipment compartment, its design, and construction method. The foundation structure includes prefabricated corbel columns, prefabricated connecting beams, and connecting components. Multiple sets of prefabricated corbel columns are arranged in an array at intervals. Prefabricated connecting beams are provided between adjacent sets of prefabricated corbel columns, and these beams are connected to the prefabricated corbel columns via connecting components. The prefabricated foundation structure for an energy storage power station equipment compartment provided by this invention can significantly shorten the construction cycle and reduce construction costs. By standardizing the production of prefabricated components in a factory, on-site casting work is reduced, avoiding time-consuming processes such as traditional on-site casting formwork and curing, improving construction efficiency and quality stability, and reducing the difficulty of quality control. Furthermore, compared to traditional on-site cast-in-place foundations, this solution can reduce on-site material waste, avoid dust and noise pollution and construction waste accumulation, saving resources and being environmentally friendly.

The invention belongs to the technical field of flight simulation training, and provides a portable virtuality and reality combined flight skill enhancement training cabin, which comprises a hardware framework for simulating the size and layout of an aircraft cockpit, and a cockpit electrical device, a display control device and a control mechanism are arranged in the hardware framework; the hardware framework comprises a cockpit bottom support, a cockpit floor, a simulation seat, an instrument board and a display support, the cockpit floor is arranged above the cockpit bottom support, and the cockpit floor provides simulation of the bottom space in the aircraft cockpit; the position and the structure of the simulation seat restore the flight seat; the instrument panel and the display bracket are arranged in front of the simulation seat; the cabin electrical equipment comprises head display equipment and cabin equipment, and virtual visual simulation is provided for the part, without the simulated airplane, of the enhanced training cabin body hardware; the display control equipment is arranged on the display bracket and is combined with the cabin electrical equipment to provide the same display content of the aircraft display; the control mechanism comprises a left-right control board. The system is integrally designed based on a modular design thought, and the whole training cabin is low in cost, good in training effect and simple and convenient to use and maintain. By constructing a hardware framework and physical equipment in the cabin, simulation of the portable virtuality and reality combined flight skill enhancement training cabin is realized.

The utility model relates to a kind of lifting reciprocating components for stuffing forming machine material receiving, the component includes base, side plate, guide rail, sliding block, cutter disc lifting plate, belt lifting plate, cutter disc lifting motor and belt lifting motor, two side plates are vertically fixed in the both ends of base, its inboard is equipped with guide rail, sliding block is mounted on guide rail, sliding block is connected cutter disc lifting plate between, cutter disc lifting motor drives cutter disc lifting plate to reciprocate along guide rail up and down by first crank link mechanism, belt lifting motor drives belt lifting plate to move up and down by second crank link mechanism, belt assembly is provided on belt lifting plate, symmetrically equipped with guide rod on belt lifting plate, guide rod is fixedly arranged in guide seat on base, and its top end is provided with lower supporting plate and upper supporting plate for carrying belt assembly, the utility model realizes the independent accurate lifting of cutter disc and material receiving belt and collaborative operation, movement is stable, material receiving is reliable, effectively improve the production efficiency and product quality of stuffing forming machine.

The invention relates to an etching device for a printed circuit board of a new energy automobile, which is applied to the field of circuit board etching and comprises a cylindrical etching liquid box, a driving motor is mounted on the etching liquid box, a rotating rod is mounted at the output end of the driving motor, and a sliding assembly is mounted between the rotating rod and the etching liquid box. A linkage mechanism comprising a mounting seat, a clamp, a slow gear and a transmission assembly is mounted on the sliding assembly, a slow gear path meshed with the slow gear is mounted on the inner wall of the lower half part of the etching liquid box, and the mounting seat is driven by a driving motor to do circular motion, so that continuous etching and taking and placing operation of a circuit board are facilitated; after the circuit board moves into the etching liquid on the inner side of the etching liquid box along with the mounting seat, the slow gear rotates under the meshing action of the slow gear and the slow tooth path, and the rotating slow gear enables the clamp to drive the circuit board to rotate through the transmission assembly, so that the fluidity of the etching liquid on the surface of the circuit board or in the etching groove is enhanced; therefore, a sufficient etching effect is ensured.

This utility model relates to a knot-making machine, and more particularly to a rope-cutting device for the knot-making machine, solving the automation problem of rope cutting in knot-making machines. It includes a machine base, on which are provided a material guiding mechanism, a material placement rack, a material conveying mechanism, and a rope-cutting mechanism for cutting and transferring materials. The rope-cutting mechanism includes a support, a transverse guide rail, a slide, and a pneumatic clamp. The transverse guide rail is fixedly mounted on the machine base via the support. The slide and the transverse guide rail, and the pneumatic clamp and the slide, are in a limited sliding fit, with the movement directions of the pneumatic clamp and the slide perpendicular. A linkage lifting mechanism is also provided between the pneumatic clamp and the slide. The lifting mechanism includes a lifting motor, a crank, and a connecting rod. The lifting motor is fixedly mounted on the slide, and the output shaft of the lifting motor is fixedly assembled to one end of the crank. The design is simple and reliable, with a high level of automation. Through pneumatic clamping and transfer and cutting with a blade, the rope cutting is stable and efficient, meeting the user's production needs and possessing practicality and economy.

The invention relates to a rear bracket and suspension system for a driving motor, and the system comprises a front auxiliary frame which is a metal plate welding part and comprises an auxiliary frame body, and the left end of the auxiliary frame body is fixedly provided with a left front supporting arm and a left rear supporting arm which are used for connecting a left longitudinal beam assembly; a right front supporting arm and a right rear supporting arm which are used for being connected with a right longitudinal beam assembly are fixedly arranged at the right end of the auxiliary frame body. The rear suspension support is a sheet metal part which is integrally punched and formed and is welded in the middle of the front end of the auxiliary frame body, the rear suspension support comprises a left mounting plate, a right mounting plate and a connecting plate, the left mounting plate and the right mounting plate are parallel to each other and arranged at an interval, the connecting plate is connected between the left mounting plate and the right mounting plate, and flanges are arranged on the outer edges of the left mounting plate and the right mounting plate. According to the front auxiliary frame, a stamped and tailor-welded metal plate structure is adopted, functions are integrated, and the structure is light. The rear suspension support is a sheet metal part which is integrally punched and formed and is welded in the middle of the front end of the auxiliary frame body, and the structural design of the rear suspension support meets the modal and strength requirements of the suspension support.

The invention discloses a pod propulsor structure optimization design method based on data driving. Comprising the steps of defining a design variable and an optimization target, constructing a parameterized geometric model, building a full-process automatic simulation analysis framework, generating a sample space through experimental design, obtaining a complete sample data set, constructing a high-precision agent model, carrying out algorithm optimization based on the agent model, verifying optimal design and calculating a data closed loop. And continuously updating the model. According to the method, the trained data driving agent model is utilized, in a huge design space, performance evaluation can be completed only in an extremely short time, the calculation period is greatly shortened, and a global optimal solution set can be rapidly obtained in combination with a global optimization algorithm; according to the method, various factors such as design requirements, test design, an agent model construction method and an optimization algorithm are comprehensively considered, the method can be suitable for structural design of other pod propellers with different production models or different design requirements, and effective guidance is provided for subsequent design of the pod propellers.

The invention relates to a pulsation damper for damping vibrations of a pressure medium in a hydraulic system, for which purpose the pulsation damper has a membrane (1) in a bore (13) of a housing (15), which is exposed on one side to the pressure medium and on its other side faces a gas-filled chamber (12) in the housing (15), the bore (13) being closed by a plug (2). The membrane (1), together with the plug (2) and a hollow cylindrical support body (3), form an independently operable, functionally pretestable assembly, for which purpose the membrane (1) is substantially pot-shaped and the support body (3) extends into it.

The invention relates to the technical field of aviation turboshaft engines, and provides a thermal damage number-based aviation turboshaft engine load spectrum design method, which comprises the following steps of: analyzing power requirements in each typical mission profile by adopting an engine performance model according to information of a plurality of typical mission profiles of an engine; obtaining the engine state and duration of each mission profile in the first application scene, namely engine load spectrum parameters in the first application scene; fitting a relational expression between the accumulated thermal damage of the working blade of the gas turbine of the engine and the # imgabs0 # temperature; based on the relational expression, calculating accumulated heat damage of the engine in the first application scene under different # imgabs 1 # temperature duration time in each state; and the engine is applied to a second application scene, the accumulated heat damage is kept unchanged, and the lasting time and the time proportion of all states of the engine in the engine load spectrum are obtained, namely, the engine load spectrum parameters in the second application scene are obtained. When each state of the newly developed engine is equivalently converted, the problems of reasonability and accuracy of conversion can be effectively solved.

The utility model discloses a self-balancing track type crane anchoring device. The self-balancing track type crane anchoring device comprises an anchoring frame, a lower box body, a floating plate, a control assembly, a bolt and an anchoring seat, the anchoring frame is of an isosceles triangle truss structure which is vertically and transversely arranged, and the two waist edges of the anchoring frame are arranged downwards and connected with the upper surface of the lower box body. A floating plate is horizontally and longitudinally arranged in the middle of the upper surface of the lower box body and between the two waist edges of the anchoring frame, the floating plate is horizontally and rotatably connected with the lower box body around the center, and the front and rear ends of the floating plate extend out of the front and rear surfaces of the lower box body; bolts are vertically arranged on the upper surface of the floating plate relative to the front side and the rear side of the lower box body, the lower ends of the bolts vertically and downwards extend out of the lower surface of the floating plate, anchoring seats are arranged on the ground relative to the positions of the two bolts, and the bolts are vertically and slidably connected with the floating plate through driving of a control assembly; and the lower ends of the bolts are inserted into the corresponding anchoring seats. According to the utility model, the loads of the two bolts can be automatically balanced.

The invention relates to a platform type laser ranging angular position measuring system, and belongs to the technical field of laser ranging. The device for measuring the angular position is placed in the electronic cabin through the laser distance measuring device, the laser beam is emitted through the distance measuring device, the laser return time is measured, and the relative position of the movement mechanism of the optical cabin is determined. According to the laser ranging type angular position measuring system, heading and pitching potentiometers or rotary transformers are omitted in the optical cabin. Compared with an existing potentiometer position measuring system, the laser ranging type angular position measuring system is simple in structure, simple in algorithm and small in occupied space, meanwhile, a movement mechanism is simplified, and the reliability of a product is improved. The system calculates a corresponding motion position through a calculation process of the laser ranging system. The design scheme is simple and reliable, and has obvious advantages in miniaturized product design.

The present application relates to the technical field of ultra-precision machining control, and particularly relates to a modal controller generation method for a nano-positioning platform, a medium and equipment. The present application performs zero-pole decomposition on a transfer function of a controlled object, separates stable zero points, unstable zero points, non-resonant poles and resonant poles, constructs a desired inner loop closed-loop transfer function, retains the stable zero points, the unstable zero points and the non-resonant poles, and replaces the resonant poles as a whole with high-damping desired poles, inversely solves to obtain a modal controller structure, introduces zero-pole cancellation constraints to eliminate controller instability caused by unstable zero points, introduces order constraints to ensure causal realizability, applies constraints with a damping ratio greater than 0.1 to the desired poles and the introduced new zero points respectively, and outputs an inner loop modal controller. The present application realizes simultaneous suppression of multiple resonant peaks, gets rid of dependence on a low-order model, ensures stability, realizability and smoothness of a control signal of the controller, and significantly improves control bandwidth and dynamic performance.

The present invention relates to an evolutionary algorithm-assisted safety PID controller design method considering network hybrid attacks, which solves the problems of slow response speed, insufficient robustness and heavy computational burden of traditional methods. The specific steps include: establishing a discrete time network control system model, defining state vector equations and output equations; defining a hybrid attack network model; designing an observer-based PID controller, and using GA genetic algorithm and LMI linear matrix inequality to obtain the PID controller gain and observer gain to be designed; using an event trigger mechanism to determine whether to transmit the output of the PID controller to an actuator; and realizing stabilization of the UAV system according to the output of the actuator. The present invention improves the robustness and response speed of the UAV control system when facing hybrid attacks, reduces the computational and communication burdens, and ensures the safe and stable operation of the UAV in a complex environment.

The utility model discloses an air inlet compensation device for a centrifugal compressor, and relates to the field of centrifugal compressors. The device is mainly composed of a wake flow correction pipe, a main flow pipe, a bearing, a motor, a rotating body, an impeller, a shell, a filter screen and the like, the wake flow correction pipe is connected with the main flow pipe through a sleeve, the shell and the main flow pipe are sealed through a sealing ring, and the impeller, the rotating body and the motor are sequentially nested and fixed to the main flow pipe through the bearing. All main parts in the device share the same central axis, so that the overall layout is reasonable, and the structure is compact. When the air pressure of an inlet of the centrifugal compressor is low, the device can increase the air inflow of the centrifugal compressor through the auxiliary flow channel, so that the centrifugal compressor works under the designed working condition with the highest efficiency; when the inlet air pressure of the centrifugal compressor meets the designed working condition value, the device can stop working under the condition that the original air inlet mode is not affected. The motor type and the impeller type in the device can be replaced according to different working scenes, and the application range of the device is greatly widened.

The invention provides an optimization design method, device, equipment and medium for a multi-dimensional functionally graded material, and belongs to the technical field of functionally graded material design, the method comprises the following steps: constructing the multi-dimensional functionally graded material based on a non-uniform rational B-spline basis function; the multi-dimensional functionally graded material comprises a plurality of control points; constructing a sample set, and training the initial material prediction model based on the sample set to obtain a completely trained material performance prediction model; constructing a multi-objective optimization function by taking the minimum total mass and the maximum free vibration fundamental frequency as objectives, and carrying out iterative solution on the multi-objective optimization function to obtain the volume fraction and the optimized thickness of a control point optimized material; wherein the prediction performance required in the iterative solving process of the multi-objective optimization function is determined based on the material performance prediction model. According to the method, the data volume in a multi-objective optimization algorithm is reduced, and rapid and reliable optimization design of the multi-dimensional functionally graded material with relatively high design dimension and relatively many design variables can be realized.

The utility model discloses a self-balancing windproof inhaul cable device for a crane. The self-balancing windproof inhaul cable device comprises a balance beam, an inhaul cable, a connecting plate and a base, a balance beam is horizontally and longitudinally arranged in the middle of the bottom of the cart traveling mechanism which is horizontally and transversely arranged, and the middle of the upper end of the balance beam is vertically and rotatably connected with the cart traveling mechanism in the longitudinal direction; inhaul cables are further vertically and symmetrically arranged under the balance beam relative to the front side and the rear side of the cart walking mechanism, and the upper end of each inhaul cable is vertically and rotationally connected with the front end and the rear end of the balance beam in the longitudinal direction; the lower end of each inhaul cable is vertically and rotationally connected with the upper end of the corresponding connecting plate in the transverse direction, bases are further arranged on the ground corresponding to the positions of the two inhaul cables, and the lower end of each connecting plate is vertically and rotationally connected with the upper end of the corresponding base in the transverse direction. And the loads of the inhaul cables on the two sides are kept balanced all the time through free rotation of the balance beam. According to the utility model, the loads of the two inhaul cables and the two bases can be kept balanced all the time.

The invention discloses a space laser communication transceiving system and method with a multi-wavelength self-loop test function, and solves the problem that after a laser communication load is launched into an orbit, rapid on-orbit self-inspection cannot be carried out on optical communication transceiving subsystem devices, modules, circuits and the like in the prior art. By switching the polarization state of the high-speed laser signal and utilizing the principle that the polarization beam splitter group reflects S light and transmits P light, a self-test loopback light path is formed for the emitted multi-band high-speed laser signal, the self-test test of the satellite can be realized before double-satellite link establishment is implemented, the emission light path is not influenced, and the measurement accuracy is improved. According to the method, the on-orbit state of the optical communication transceiving subsystem can be judged through single-byte telemetering data only by switching the laser polarization state, and on-orbit self-inspection testing can be rapidly and effectively completed under the urgent conditions that the transit time of a satellite is short and the number of testing steps is large.

This invention proposes a method and system for predicting the drag contribution of automotive rear wing designs, belonging to the fields of automotive aerodynamics and artificial intelligence. The method includes: acquiring and preprocessing raw CFD flow field images to generate standardized binary images; extracting flow field depth and tilt angle features from the binary images, using them together as multi-source features characterizing the wake field structure; constructing a deep learning model, using the multi-source features as input, training the deep learning model, and outputting scalar parameters; inputting the flow field image of the automotive rear wing design to be predicted into the trained deep learning model, extracting multi-source features, and combining them with changes in target design parameters to quickly predict the drag contribution using a quadratic function. This invention significantly improves prediction efficiency and has strong generalization ability, providing accurate and efficient decision-making basis for automotive rear wing drag optimization design, and is suitable for rapid iteration and parameter scanning in automotive rear wing design.

The utility model discloses a copper powder stirring barrel feeding alignment auxiliary device, including work table, discharge pipe, receiving pipe and the rotation type mixer between them, and the receiving pipe mouth is coaxial with double -tube. The upper butt joint device is established below the discharge pipe, and the symmetrical lower butt joint device is established above the receiving pipe, and all contain sliding device, butt joint cylinder, alignment platform, ear seat, butt joint pipe and butt joint, and the ear seat is symmetrically established in alignment platform both sides, and the butt joint cylinder is hinged in the ear seat. The butt joint pipe is connected the discharge pipe or receiving pipe through the hose, and the upper butt joint is established below the alignment platform, and the receiving pipe mouth is equipped with the lower butt joint, and the radial homocentricity is guided through the upper / lower butt joint cone surface contact, and the sliding device displacement compensation radial deviation, and the butt joint cylinder drives the alignment platform to deflect and correct the angle deviation around the ear seat, ensures the receiving pipe mouth and butt joint pipe accurate closure in the dynamic operation of the rotation mixer, solves the problem of low fault tolerance of traditional vertical butt joint.

The invention provides an energy-gathered jet flow forming and stability analysis method, which comprises the following steps of: performing jet flow forming analysis on energy-gathered jet flow formed by crushing a shaped charge liner by detonation waves generated by explosive initiation so as to establish a relationship among shaped charge liner structure parameters, a jet flow diameter, a temperature and a strain rate; performing jet flow stability analysis on the energy-gathered jet flow to determine a jet flow stability loss criterion; and finally, the jet flow fracture time is obtained. According to the method, the relation between the shaped charge liner structure parameters and the jet diameter, temperature and strain rate is established, a jet stability criterion and jet fracture time evaluation method comprehensively considering strain hardening, the strain rate effect, the heat effect and the necking effect is provided, and an analysis method of the shaped charge liner structure parameters on the jet stability is constructed. And the jet stability is effectively analyzed.

The present application provides a container-type mobile surfacing welding device, comprising a container body (10), characterized in that the container body (10) comprises a first functional area (1), a second functional area (2) and a third functional area (3), wherein the first functional area (1), the second functional area (2) and the third functional area (3) are arranged inside the container body (10) and arranged in sequence. The container-type mobile surfacing welding device provided by the present invention has a design of each component that is lighter and more reliable than traditional equipment, and all of these components are integrated into one container, making cargo transportation and on-site preparation simple. In practical applications, on-site construction time can be saved, the number of workers can be reduced, and the equipment maintenance cost of the mill user can be ultimately reduced.

The present invention relates to the technical field of hydrogen storage cylinders, and discloses a design method for a type IV large-volume hydrogen storage cylinder, comprising the following steps: determining the service parameters and structural parameters of the hydrogen storage cylinder; designing the structure of the composite winding layer of the hydrogen storage cylinder to obtain N laying schemes of the composite winding layer; for the winding layer formed by each laying scheme, analyzing the mechanical response of the winding layer under three key working conditions of rated working pressure, water pressure test pressure and minimum bursting pressure, and obtaining the dangerous parts of the winding layer under different working conditions; analyzing and evaluating the dangerous parts based on the maximum stress failure criterion, and selecting the optimal laying scheme of the winding layer based on the evaluation results; constructing a theoretical model of the inflation of the hydrogen storage cylinder; applying the model to simulate the transient inflation process of the hydrogen storage cylinder to obtain the temperature rise evolution law of the hydrogen storage cylinder; and formulating a temperature control strategy based on this. The present invention is suitable for the design of hydrogen storage cylinders for long-tube trailers, and takes into account the temperature rise evolution law during the filling process, and has the advantages of safety and reliability.

The invention discloses an ultrahigh-frequency ultrasonic transducer capable of generating quasi-unipolar pulses, and belongs to the technical field of ultrasonic transducers. The transducer comprises a backing layer, a high-frequency piezoelectric layer and a combined layer which are sequentially arranged from bottom to top. The combined layer comprises an acoustic decoupling layer, a first high-frequency matching layer, a second high-frequency matching layer, an ultrahigh-frequency piezoelectric layer, an ultrahigh-frequency polymer matching layer and an ultrahigh-frequency metal matching layer. A penetrating cavity is arranged between the first high-frequency matching layer and the second high-frequency matching layer, and an acoustic decoupling layer, an ultrahigh-frequency piezoelectric layer, an ultrahigh-frequency polymer matching layer and an ultrahigh-frequency metal matching layer are sequentially arranged in the penetrating cavity in a stacked mode. During working, the high-frequency piezoelectric layer and the ultrahigh-frequency piezoelectric layer can be driven to generate forward waves of high-frequency ultrasonic waves and ultrahigh-frequency ultrasonic waves respectively by reasonably adjusting electric excitation parameters, and the forward waves of the high-frequency ultrasonic waves and the ultrahigh-frequency ultrasonic waves are superposed, so that quasi-unipolar pulses with sharp main lobes and low side lobe levels are synthesized. The problem of pulse trailing of the ultrahigh frequency transducer is effectively solved, the axial resolution is remarkably improved, and meanwhile high detection sensitivity is kept.

The invention relates to a hair styling appliance, the blowing head (10) of which comprises a housing (6A) and carries a first and a second blowing outlet (2, 3), an air guide member (18) for alternately guiding an air flow towards the first or second blowing outlet, a system for controlling the air guide member, the latter being arranged in a first part of the housing, the control system being arranged in a second part of the housing, the housing carries a first peripheral wall (22) arranged in contact and surface overlap with a second peripheral wall (24) carried by the fixed portion of the control system to prevent passage of air from said first portion to said second portion in a direction parallel to an average direction of entry of the airflow in the air guide member.

The invention belongs to the field of bioinformatics, and particularly relates to a prediction transcript screening method and device for reference-genome-free species. In order to solve the problems that existing software and methods are insufficient in pseudo transcript recognition capacity and high in false positive, the novel transcript screening method is provided and comprises the steps of obtaining input data, preprocessing the data, conducting BUSCO conserved gene matching, conducting ORF integrity detection, conducting ORF homology judgment, conducting ORF length detection and conducting statistical scoring through a fusion confidence coefficient function. And obtaining a final score F of the predicted transcript. The invention provides an efficient, universal and low-use-threshold prediction transcript screening method for reference-free genome species, and the screened transcript is real and reliable, has both efficiency and practicability, and is expected to become a key method for improving efficiency and gene research accuracy of bioinformatics and molecular biology workers in the future.