52 results about "Nonlinear property" patented technology

An ultrasonic ranging method for measuring a distance to an object in an air includes the steps of generating a first and a second primary ultrasonic waves having a frequency f₁ and f₂, respectively, transmitting the first and the second primary ultrasonic waves in a same direction, wherein a secondary ultrasonic wave having a frequency corresponding to the difference of two frequencies f_d=f₁−f₂ is created by a nonlinear property of the air and radiated to the object, detecting an echo pulse of the secondary ultrasonic wave reflected from the object, and measuring the distance to the object based on a propagation time of the secondary wave.

The invention relates to the field of linear motor control, in particular to a method for restraining the pulsation of a thrust system of a linear motor; the method adopts a sliding mode thrust controller and a magnetic flux controller, the thrust deviation and the magnetic flux deviation are selected as controlled variables, an integral sliding mode surface which is composed of the thrust deviation and the magnetic flux deviation design the sliding mode motion trajectory, thereby a system can move according to the sliding mode trajectory and the output thrust and the magnetic flux can better track specified value, wherein, a fuzzy controller utilizes the fuzzy control method which uses language information and data information to approach any specified continuous function to solve the jitter problem of a sliding mode control system. The method has the advantages that: a direct drive control system of the linear motor has strong coupling property, nonlinear property, multiple variables and unique end effect, the use of the direct thrust control method of the fuzzy sliding mode linear motor with high robust performance can solve the impacts of various factors on the control performance, thereby achieving the purposes of restraining the thrust pulsation of the linear motor and obtaining great dynamic response performance.

The invention discloses a nonlinear inverse control method used for dynamic hysteresis compensation of a piezoelectric actuator. Nonlinear inverse control of the piezoelectric actuator is performed based on a Prandtl-Ishlinskii model by aiming at the problem that most models cannot perform accurate inverse analysis for the modeling difficulty of a dynamic hysteresis system; a dynamic critical value related to the input frequency is established to obtain a rate-dependent play operator, and the rate-dependent play operator is combined with a density function so as to obtain a rate-dependent Prandtl-Ishlinskii model; a hysteresis main ring is measured under different input frequencies so as to determine model parameters; the inverse parameters of the model are inversely solved by solving an initial load curve so as to obtain a rate-dependent Prandtl-Ishlinskii inverse model; and the Prandtl-Ishlinskii model and the inverse model thereof are used for an open-loop control system so as to compensate the hysteresis nonlinear property of the piezoelectric actuator. The experiment proves that the rate-dependent Prandtl-Ishlinskii model can accurately describe the hysteresis nonlinearity of the piezoelectric actuator and the rate-dependent Prandtl-Ishlinskii inverse model enhances the positioning and control precision of a hysteresis nonlinear system.

The invention relates to the technical field of civil engineering, in particular to a damper and a manufacturing method thereof. A high-damping rubber fluid viscoelastic damper comprises a steel plate layer and a fluid viscoelastic material layer, wherein the steel plate layer comprises a middle steel plate and side steel plates arranged at two sides of the middle steel plate, the fluid viscoelastic material layer is arranged between the steel plate layer and the side steel plates, and the fluid viscoelastic material layer is the high-damping rubber fluid viscoelastic material layer made of high-damping rubber fluid viscoelastic material. Due to the adoption of the technical scheme, the invention has the following advantages: the vibration energy can be absorbed effectively by the deformation of the high-damping rubber fluid viscoelastic material, a hysteresis ring is full, and the fatigue resistance is good; and compared with the traditional fluid viscoelastic damper, the energy consumption property has stronger nonlinearity, and the energy consumption property is good under the condition of extremely small displacement and extremely low speed.

A distortion compensation apparatus and an apparatus and method for transmitting a signal are provided. The distortion compensation apparatus can extract precise distortion information by adding an additional signal to an input signal during the compensation of distortion in a nonlinear apparatus, and can linearize the nonlinear properties of the nonlinear apparatus using the distortion information. The apparatus for transmitting a signal can output a signal linearized by the same method as that used by the distortion compensation apparatus.

The invention relates to a method for constructing the index for content-based heavy-capacity picture fast search, belonging to an intelligent information processing technique. In the existing techniques, the searching efficiency is low and the system robustness is not strong enough. For this, on the basis of balancing the index structure of multipath search trees, the invention introduces a clustering regulation mechanism and advances a minimum complete subtree updating policy and a nonlinear property quantization algorithm. The invention will largely enhance the performance of the index structure, reduces search response time and enhances the system robustness, and has an important application value in the content-based heavy-capacity picture fast searching system.

The invention discloses a synthetic aperture radar (SAR) image classifying method based on stacked automatic coding machines, belongs to the technical field of radar image classification, and solves the problem of low classifying precision of SAR image data due to serious noise pollution and nonlinear property. The method comprises the following steps: firstly, acquiring N original SAR images for data preparation to obtain SAR image data and SAR supervision data; secondly, obtaining training image data and test image data according to the SAR image data; thirdly, obtaining training monitoring data and test monitoring data according to the SAR supervision data; fourthly, pre-training all layers of the automatic coding machines by the training image data, performing supervised learning on a network by the training supervision data on the basis of pre-training, and finely adjusting the network to obtain the trained network based on the stacked automatic coding machines; finally, inputting the test image data into the trained network based on the stacked automatic coding machines to classify the SAR images. The method is used for classifying the SAR images.

In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region (130) remote from a borehole using a conveyed logging tool (140) is disclosed. In some aspects, the method includes arranging a first source (105) in the borehole (110) and generating a steered beam of elastic energy at a first frequency; arranging a second source (115) in the borehole (110) and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location (130) away from the borehole (110); receiving at the borehole (110) by a sensor (135) a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole (110).

The invention provides a negative stiffness element with automatic balance position adjusting capacity and a negative stiffness property generation method and application, and relates to the field ofground-based simulation of gravity environment. The negative stiffness element with automatic balance position adjusting capacity and the negative stiffness property generation method and applicationare purposed to solve the problem of variation of mechanical property, caused by variable mass load, of a balance position of an existing high static and low dynamic stiffness supporting system; the dynamic stiffness of the new system is reduced on the premise that the original system balance position is not influenced so as to ensure that the stable balance position of the system in static loading process is the same as that of an original system; when dynamic load acts on the system, the system stiffness is the value of difference between the original system stiffness and the negative stiffness element stiffness. The geometric nonlinear property and adjustable geometric parameter property of a mechanism are utilized, the transverse spring stiffness and the effective length of a roller mechanism are properly set to realize the special negative stiffness property; a mechanism housing and a central vertical column are locked and unlocked to realize the negative stiffness property of opening and closing elements in a special condition. Therefore, the problems that the static displacement beyond the limit due to excessively low system stiffness or the mechanical property of a balancepoint of a quasi-zero stiffness system is damaged due to excessively low system stiffness can be avoided.

The invention relates to a niobium oxide gating appliance based on zirconia tunneling layer and its manufacturing method. The gating appliance orderly comprises a bottom electrode layer, a zirconia tunneling layer, a niobium oxide converting layer and a top electrode layer from bottom to top; the thickness of the bottom electrode layer is 50-300nm, the thickness of the tunneling layer is 1-5nm; the thickness of the converting layer is 30-100nm and the thickness of the top electrode layer is 50-300nm; the tunneling layer, the converting layer and the top electrode layer are formed by a magneticcontrol sputtering method. A layer of ultra-thin zirconia tunneling layer is added between the niobium oxide converting layer and the bottom electrode layer, the zirconia tunneling layer effectivelyreduces the operation current and operation voltage of the appliance, thus the using consumption of the appliance is significantly reduced, the high-impedance state resistance value is increased, andthe nonlinearity is promoted; therefore, the gating appliance is high in nonlinear property value and is of great development potential and application value.

To obtain an optical component having excellent secondary optical nonlinear properties by irradiating a surface and/or inside of glass having at least one member selected from Ni, Fe, V, Cu, Cr and Mn as a heat source material for absorbing and converting a laser beam to heat, incorporated to a glass matrix comprising at least one glass-forming oxide-selected from SiO₂, GeO₂, B₂O₃, P₂O₅, TeO₂, Ga₂O₃, V₂O₅, MoO₃ and WO₃ and at least one member selected from alkali metals, alkaline earth metals, rare earth elements and transition elements, with a laser beam with a wavelength to be absorbed by the heat source material, to convert the irradiated portion to a single crystal or a group of crystal grains comprising components contained in the glass matrix and not containing the heat source material, thereby to form a pattern.

The invention belongs to the field of transition metal polymers, and in particular relates to a three-dimensional coordination polymer nonlinear optical material of which the chemical formula is {[Mn(HPIDC)](H2O).2H2O}n, wherein in the formula, HPIDC is divalent anion of 2-(4-pyridyl)-1H-imidazole-4,5-dicarboxylic acid. The secondary harmonic effect (SHG) of the three-dimensional coordination polymer nonlinear optical material is 1.5 times of that of a standard sample potassium dihydrogen phosphate (KDP), and the three-dimensional coordination polymer nonlinear optical material has certain second-order nonlinear properties, has the potential to be a nonlinear optical material, and has wide application prospects in fields such as optical information storage, laser communication, electronic instruments and medical instruments.

A method and apparatus are provided for measuring samples of the electric field of light propagated through a device under test and determining a nonlinear property of the device, such as self-phase modulation or cross phase modulation, using the measured samples.

A high temperature magnetic amplifier, which utilizes the nonlinear properties of square loop magnetic cores to achieve very large amounts of both voltage and power amplification. By combining square loop, grain-oriented magnetic materials with high temperatures along with high temperature packaging approaches, high temperature long lifetime components can be produced. The high temperature magnetic amplifier is used as a building block to develop high temperature versions of operational amplifiers, comparators, voltage regulators, timers, counters, modulators, motor starters, servo systems, converters, inverters, power switches and many other devices.

The invention discloses an automatic reset differential pressure module and a method for measuring wind speed and wind direction. The module comprises an automatic reset component and a micro differential pressure element; the micro differential pressure element is provided with a sampling port I and a sampling port II; the automatic reset component is provided with an interface I, an interface II and an interface III; the interface I and the interface III can be in communication with the interface II through an electrical controlled and driven switching way, or be closed; a detection device in the invention adopts the structure of the automatic reset component, and is suitable for measuring the wind speed and the wind direction in extremely poor working conditions such as in coal mine and the like, the measuring accuracy and the stability are higher, a zero point calibration function is achieved, the structure is simple, the processing and the assembling are easy, the using period is longer, the use cost is saved, the nonlinear property of delaying after full range work of a diffused silicon pressure sensor is eliminated, the use proves that zero point variation is less than 0.1 Pa within the range of 0 to 40 DEG C, and stable measuring of 0.1 Pa can be achieved.

A hard disk drive limit stop is designed with bilinear-nonlinear properties including a second element between a collar and the actuator. The second element has characteristics that are desired for a self servo write (SSW) start-up process. The limit stop has a crown, such as a cantilever spring, that is mounted to the collar. The stiffness of the crown gives the desired motion under the electrical current applied to the voice coil. The crown is made from material that does not stick to the actuator. Alternatively, the limit stop is used for SSW only, then rotated out of the way so that it is not used during normal operation of the hard disk drive. The SSW limit stop moves out of the way after SSW is complete so that another limit stop may be used during operation.

The invention relates to a preparation method of a zinc oxide-bismuth oxide thin film varistor, and belongs to the technical field of preparation and application of electronic information materials. The preparation method includes the steps that with non-stoichiometric sintered ZnOn (n<1) as a matrix target and other metals or oxides thereof as doped targets, deposition is carried out on a conductive substrate with a radio-frequency magnetron sputtering method and an optimized sputtering technology, and a low-resistivity zinc oxide thin film is obtained; then, the zinc oxide thin film is buried in bismuth oxide powder for hot dipping, and the zinc oxide-bismuth oxide thin film varistor is obtained. The thin film varistor has the advantages of being excellent in nonlinear property, controllable in varistor voltage, small in leak current and the like, and has broad application prospects in overvoltage protection of large-scale or super-large-scale integrated circuits. According to the method, thin film deposition and hot dipping conditions are strict and controllable, technological repeatability is good, the thin film device uniform in composition, structure and thickness can be obtained on the large-area substrate, and the method is suitable for large-scale production.

The invention discloses a Matlab based simulation control method for a nonlinear backstepping controller. The method includes steps of (1) constructing a mathematic model of a magnetic suspension ball system in a way of neglecting other interference that may act on the ball; (2) constructing a nonlinear backstepping controller model of the magnetic suspension system and obtaining a conclusion that all tracking errors level off to zero according to LaSalle invariant theory. System stability is improved and the control rate of the backstepping controller is given by a formula (8, 9, 10). According to the invention, the magnetic suspension ball system having highly nonlinear property has good stability and high-performance location tracking capability. The adopted method is effective, and is high in modeling precision and insusceptible to external interference.

The invention relates to a method for inducing and separating out orientation controllable lithium niobate single crystal in glass by using femtosecond laser, belongs to the technical field of laser application, and also belongs to the technical field of new material development. The lithium niobate single crystal is induced and separated out under the irradiation of the femtosecond laser by adopting an ytterbium-doped optical fiber amplifier and a frequency adjustable laser device. The method is characterized in that: femtosecond laser beams are focused at 100 to 1,000 microns below the surface of the glass through a focusing lens, the lithium niobate single crystal can be selectively induced and separated out in the glass by strictly controlling the frequency of laser, the pulse energy, the modifying direction of the laser, the scanning speed and the scanning direction, and the growing orientation of the lithium niobate single crystal can be controlled; and the femtosecond laser has the control parameters that: the wavelength is 1,030 nanometers, the frequency is 250 to 500KHz, the pulse width is 240 to 300fs, the pulse energy is 0.5 to 2.5muJ, the numerical aperture of the focusing lens is 0.4 to 0.8, the scanning speed is 0 to 210mum/s, and the modifying direction of the laser is controlled through a polarizer. The induced and separated lithium niobate single crystal is an excellent ferroelectric material; and because of photoelectric, pyroelectric, piezoelectric, photorefractive and nonlinear properties, the lithium niobate single crystal has broad application prospect in the fields of acoustics and optics, photo-electricity, nonlinear optics and the like.