82 results about "Nonlinear phenomena" patented technology

The invention provides a design method for a sliding mode disturbance observer used for servo system control, and aims at the friction interference problem in low speed of a servo system and considers the error and uncertainty problem of system modeling. A common DC motor model is used, and a disturbance observer and sliding model variable structure control are combined so that the sliding mode disturbance observer is designed. Firstly the size of the friction torque is observed by using the disturbance observer, and then a sliding mode controller is designed according to the obtained friction torque. The switching item gain of the sliding mode controller can be reduced through observation of friction torque so that the buffeting phenomenon can be reduced. Suppression of the low speed servo system for dead zone, creeping, self-oscillation and other nonlinear phenomena can be realized through the sliding mode disturbance observer so that the requirements for the modeling precision can be reduced and the method has great robustness.

A CATV station apparatus subjects received optical signals to processes such as optical-electrical conversion, signal separation, coupling, and demodulation for obtaining an uplink signal. A received photocurrent monitoring section compares a received photocurrent at a optical receiving section with a predetermined reference current. If the received photocurrent is equal to or higher than the reference current, an amplifying section amplifies a signal output from a signal separating section at a predetermined level. If the received photocurrent is lower than the reference current, on the other hand, it is determined that a non-linear phenomenon, such as stimulated Brillouin scattering, has occurred in an optical fiber. The amplifying section then outputs a signal at a level which does not affect, even after being coupled with other signals, communications performed by other optical transmission systems.

The present invention provides an optical fiber which has negative dispersion and negative dispersion slope in a wavelength band in use, and can carry out single-mode operation in which distortion due to the non-linear phenomenon can be suppressed so as to be suitable for wavelength multiplexed optical transmissions. When the relative index differences of center core (1), first side core (2), second side core (3), and inner cladding (4) from the silica level are DELTA1, DELTA2, DELTA3, and DELTA4, l.7%<=DELTA1, DELTA2<=-0.3%, 0.25%<=DELTA3, and DELTA4<0. Furthermore, the value A, determined by dividing the diameter a1 of the center core 1 by the diameter a2 of the first side core 2, is set to 0.15<=A<=0.2, and the value B, determined by dividing the diameter a3 of the second side core 2 by the diameter a2 of the first side core 3, is set to 1<B<=2. By such an arrangement, the absolute values of the negative dispersion and negative dispersion slope in a wavelength band of 1.55 mum can be made large, and in addition, light is confined within the core by the second side core (3), the effective core sectional area is made larger, and inner cladding (4) is provided, whereby the effective cut-off wavelength is shortened.

The present invention provides a pulse train generator comprising: a dual-frequency signal light source for generating a dual-frequency signal; a soliton shaper for soliton-shaping output light from the dual-frequency signal light source; and an adiabatic soliton compressor for performing adiabatic soliton compression on output light from the soliton shaper, and also provides a waveform shaper used in this pulse train generator, including a plurality of highly nonlinear optical transmission lines and a plurality of low-nonlinearity optical transmission lines which has a nonlinearity coefficient lower than that of the plurality of highly nonlinear optical transmission lines and which has a second-order dispersion value of which an absolute value is different from that of the plurality of highly nonlinear optical transmission lines. Further, the present invention provides a light source comprising a plurality of continuous light sources of which at least one oscillates in a multimode; a multiplexer for multiplexing output light from the continuous light sources; and a nonlinear phenomenon producer for producing a nonlinear phenomenon on output light from the multiplexer so as to suppress SBS (Stimulated Brillouin Scattering).

The invention proposes a non-fragile distributed fault estimation method based on a sensor network, and the method is a fault estimation method for random nonlinearity and random gain changes of a sensor. The invention relates to the design of a random gain change and random nonlinear time-varying system non-fragile distributed fault estimator. The method introduces a non-fragile distributed fault estimation problem into a nonlinear time-varying system in a sensor network environment at first. The method obtains sufficient conditions through employing the L2 gain theory and the random analysis technology, and guarantees the existing of a needed distributed fault estimator. Compared with a conventional linear fault estimation method, the method can process random uncertainty and random nonlinear phenomena at the same time, and achieves a purpose of nonlinear disturbance resistance.

An optical transmission line according to the present invention is an optical transmission line which is able to control both the waveform distortion due to the non-linearity phenomenon and the waveform distortion due to dispersion. The optical transmission line is formed by connecting, in series, the first optical fiber (8), of which the dispersion value in the set wavelength band within the 1.5 mum wavelength band is 6 to 14 ps / nm / km, and the second optical fiber (9), of which the dispersion value in said set wavelength band is -14 to -6 ps / nm / km. The dispersion slopes of the first optical fiber (8) and the second optical fiber (9) are of mutually opposite symbols. Light transmitted from an optical transmitter (11) enters the first optical fiber (8) and light which has been transmitted through the first optical fiber (8) enters the second optical fiber (9). The absolute value of the dispersion in the 1.5 mum wavelength band of each of the optical fibers (8) and (9) is set to be 6 ps / nm / km or more so as to control the four light wave mixture and said absolute value is set to be 14 ps / nm / km or less so as to control a local dispersion, in order to set at approximately zero, for the entire optical transmission line, both the dispersion value and the dispersion slope in said set wavelength band.

The invention discloses a periodic non-sinusoidal wave reference of an electronic current transformer with a current booster, comprising a main iron core of the current booster, an auxiliary iron core of the current booster, a reference main iron core, a reference auxiliary iron core, a fundamental wave power supply supplying coil, a harmonic wave power supplying coil, a primary coil, a secondary coil, a detection coil of the current booster, a compensation coil of the current booster, a reference detection coil, a reference compensation coil, a compensation mechanism, a pure resistive built-in precise resistor, an operational amplifier and a secondary coil shielding layer. By adopting the invention, the primary test current of the periodic non-sinusoidal wave for verifying the accuracy of the electronic current transformer can be generated, and the secondary standard reference voltage in linear proportional relation with the primary test current of the periodic non-sinusoidal wave can be output, the limitations of verification accuracy for the fundamental wave and the harmonic wave of the traditional electronic current transformer under the condition of the single frequency is overcome, and the non-linear phenomenon of the electronic current transformer is verified.

The present invention discloses a robust-adaptive neural network H-infinity control method of a MEMS gyroscope. A controller is designed based on a Riccati equation, and includes two parts of a basic neural network controller constructed by utilizing a strong online approximating capability of the neural network and a robust control item used for overcoming influences of external disturbance and parameter uncertainty on MEMS gyroscope system output tracking errors and ensuring system closed-loop stabilization. Parameters in a adaptive adjustment neural network system based on a Lyapunov stability theory are adopted, thus to ensure stability of the system. The controller is based on the Riccati equation, such that non-linear phenomena in the system are compensated, the precise tracking aim is achieved, stability of the system and robustness to external disturbance are raised, and industrial utility values are achieved.

The invention discloses an electrostatic control device for a resonator nanometer beam. The electrostatic control device is composed of a driving device, a single extraction device and a control device. The character that the resistance value of a graphene film sensor is changed along with bending deformation of the nanometer beam is used, changed voltage signals of the graphene film sensor serve as control input signals, and nonlinear vibration of the nanometer beam is controlled through axial control force produced by an axial parallel plate controller. The electrostatic control device aims at avoiding the harmful nonlinear phenomenon caused by electrostatic driving of the resonator nanometer beam, and therefore the vibration of the nanometer beam is similarly-linear stable vibration.

Provided are an imaging method and device for imaging using far infrared light that make it possible to quickly image a subject without producing damage or a non-linear phenomenon in the subject. A variable-frequency coherent light source is used, illumination light from the light source is irradiated onto a linear area on an imaging subject, transmitted or reflected light is used to form an image of the imaging subject, a non-linear optical crystal is used for wavelength conversion, and a one-dimensional or two-dimensional array sensor is used to image the imaging subject while the imaging subject is moved in at least one direction.

The invention discloses a double swash device for a ship liquid tank. The device comprises a horizontal swash panel, n vertical swash panels, a horizontal swash panel connecting device and a verticalswash panel connecting device; the horizontal swash panel connecting device comprises a fixed pulley, a traction steel wire rope, a fixed arm and a first motor, one end of the fixed arm is connected with the ship liquid tank, the other end of the fixed arm is connected with the fixed pulley, one end of the traction steel wire rope penetrates through the fixed pulley and is connected with the horizontal swash panel, and the other end of the traction steel wire rope is connected with the first motor; multiple through holes are formed in the horizontal swash panel and all the vertical swash panels. The device has the following advantages that occurrence of strong nonlinear phenomena such as top-hitting and rolling can be accelerated under the condition of a low liquid carrying rate, the top-hitting liquid falling time is shortened, the energy of liquid in the tank is consumed, and damage of impact load generated by sway to the tank wall is lowered.

The invention relates to a high-power multi-core optical fiber laser device. The high-power multi-core optical fiber laser device is composed of a seed resource, a pattern matcher, an amplifier and an optical fiber transmission system. The seed resource is composed of (N+1)*1 couplers, doping optical fibers and two fiber bragging gratings. The output ends of the (N+1)*1 couplers are sequentially connected with one fiber bragging grating, the doping optical fibers and the other fiber bragging grating. The pattern matcher is composed of output optical fibers and multi-core optical fibers of the seed resource and the amplifier is composed of the multi-core (N+1)*1 couplers and the multi-core doping optical fibers. The multi-core optical fibers of the pattern-type matcher are connected with the input ends of the multi-core (N+1)*1 couplers and the output ends of the multi-core (N+1)*1 couplers are connected with the multi-core doping optical fibers. Flattening or tapering flattening is conducted on the output ends of the multi-core doping optical fibers, so that the output ends of the multi-core doping optical fibers are connected with an end cap in a fused mode to form the optical fiber transmission system to output lasers. The high-power multi-core optical fiber laser device can effectively avoid the non-linear phenomenon, enables ultra-high power laser output to be achieved and has the advantages of being compact in structure, high in photoelectric conversion efficiency, stable, reliable and good in laser beam quality.

The present invention relates to an optical fiber having a configuration which enables utilization of nonlinear phenomena in the near-infrared region. The optical fiber is directed to a holey fiber having a core region extending along a predetermined axis and a cladding region with plural holes arranged along the core region. The plural holes are arranged to constitute plural layers about the core region in the cross-section orthogonal to the predetermined axis. The three holes constituting the first layer (the innermost layer) closest to the core region correspond to three vertexes from among the six vertexes of a regular hexagon and are placed such that the arrangement of the three holes has three-fold rotational symmetry. The optical fiber enables utilization of nonlinear phenomena in the near-infrared region, by properly adjusting the hole diameter d and the pitch L between adjacent holes from among the holes constituting a single layer.

The invention discloses a simple second order non-autonomous memristor chaotic signal generator, consisting of a memristor driven by a standard sinusoidal voltage signal and a capacitor parallel circuit. The circuit only comprises two dynamic elements, namely a capacitor C1 and a memristor W. The essence of the simple second order non-autonomous memristor chaotic signal generator disclosed by the invention is to replace a passive LC oscillator in a memristor Chua's circuit by using the standard sinusoidal voltage signal to constitute a simple and novel chaotic signal generator, and a chaotic attractor, a periodic limit cycle and other complex phenomena can be generated by adjusting the parameters of the circuit. The circuit is simple in structure, strong in stability and significant in chaotic properties, and plays a relatively large promotion function to the application development of the memristor circuit.

Disclosed is an orthogonal frequency division multiplexing (OFDM) optical transmitter including a signal size adjustor for amplifying plural data signals modulated based on an OFDM scheme with different amplification rates so that each data signal is amplified according to a size of the corresponding data signal. Accordingly, it is possible to reduce a peak-to-average power ratio, and thus a nonlinear phenomenon generated in an optical line can be reduced and the quality of an OFDM optical signal can be improved.

The invention relates to a chaotic signal generation circuit, in particular to a four-order memristor band-pass filter chaotic circuit which is simple in structure and capable of generating complex nonlinear phenomena, and comprises an operational amplifier U, resistors R1, R2 and R3, capacitors C1 and C2 and a second-order active generalized memristor GM, Wherein a resistor R1 is bridged betweenthe inverting input end and the output end of the operational amplifier U, a resistor R2 is bridged between the non-inverting input end and the output end of the operational amplifier U, one end of aresistor R3 is connected with the non-inverting input end of the operational amplifier U, and the other end of the resistor R3 is grounded; The positive end of the capacitor C1 is connected with the inverted input end of the U, and the negative end of the capacitor C1 is connected with the positive end of the generalized memristor GM; The positive end of the capacitor C2 is connected with the output end of the U, and the negative end of the capacitor C1 is connected with the positive end of the generalized memristor GM; And the negative end of the generalized memristor GM is grounded.

Disclosed is a waveguide type optical device utilizing a nonlinear refractive index change according to a large 3rd order nonlinear optical phenomenon. The waveguide type optical device includes a signal beam waveguide through which a signal beam propagates; and a pump beam waveguide through which a pump beam propagates, wherein the pump beam waveguide is disposed adjacent to the signal beam waveguide so that the pump beam can be coupled to the signal beam waveguide, the signal beam waveguide is made of nonlinear optical materials with large 3rd order nonlinear optical property and the pump beam waveguide is made of linear optical materials, and the wavelength range of the signal beam is different from that of the pump beam. By such a structure, the pump beam is coupled to one arm of the signal beam waveguide, thereby generating a 3rd nonlinear phenomenon on one arm of the waveguide through which the signal beam passes. Therefore, the waveguide optical device which implements an all-optical communication device operating as an optical device and can be integrated is provided.

The invention relates to a fuse with an internal buffer layer, and a manufacturing method for the fuse. The fuse comprises an insulating substrate, at least one fusing body formed on the insulating substrate, and end electrodes which are formed at the two ends of the insulating substrate and are connected with the fusing body; the fuse also comprises at least one arc-extinguishing layer which is formed in the insulating substrate and positioned around the fusing body, and at least one buffer layer which is formed on the peripheral surface of the arc-extinguishing layer or / and the peripheral surface of the fusing body; and the buffer layer is an accommodating space or has a porous structure. By adoption of the fuse with the internal buffer layer, problems of shrinkage mismatch or mutual diffusion of the fusing body and the buffer layer in a glue-discharging and sintering process can be overcome; phenomena of deformation, bending, defects and the like of the fusing body can be avoided; concentrated resistance value distribution and high fusing linearity of the fusing body are ensured, and a fusing non-linear phenomenon is avoided; and meanwhile, the normal operation of a circuit can be ensured.

The invention discloses a self-adaptive fuzzy H infinite control method for a micro-gyroscope and designs a controller by a method based on a linear matrix inequality. The controller comprises two parts, namely a basic fuzzy controller and a robust control item; the basic fuzzy controller is structured by using a fuzzy logic system and is used for approximating the ideal controller of the micro-gyroscope; the robust control item is used for overcoming the influence on the output tracking error of a micro-gyroscope system from external interference and ensuring the closed loop stability of the micro-gyroscope system. According to the self-adaptive fuzzy H infinite control method, a Lyapunov-based method is adopted for self-adaptive adjustment of parameters in a fuzzy control system so as to ensure the stability of the fuzzy control system. The controller designed by the invention is used for approximating a nonlinear equation to make up for a nonlinear phenomenon in the micro-gyroscope system to achieve the purpose of accuracy control, improves the stability and reliability of the micro-gyroscope system and achieves a high industrial utilization value.

The present invention provides provide a light power adjusting method, an optical transmitter, and an optical receiver suitable for ensuring high data transmission quality by preventing the rapid increase in SBS which occurs when the light power exceeds a predetermined value.The incident light power with which the SBS-induced backward propagating light included in the reflected light returned from the optical transmission line rapidly increases, i.e., the light power threshold is calculated.By setting the power of the light incident on the optical transmission line at a value equal to or smaller than the thus calculated light power threshold, the rapid increase in the SBS-induced backward propagating light, which is a nonlinear phenomenon of the optical fiber, is prevented.

The invention discloses a periodic non-sinusoidal wave reference of an electronic voltage transformer with a voltage booster, comprising an iron core for the fundamental wave, an iron core for the harmonic wave, a fundamental wave power supplying coil, a harmonic wave power supplying coil, a primary coil, a secondary coil, a short-circuit current-limiting resistor and an error compensation circuit. By adopting the invention, the primary test voltage of the periodic non-sinusoidal wave for verifying the accuracy of the electronic current transformer can be generated, and the secondary reference voltage in linear proportional relation with the primary test voltage of the periodic non-sinusoidal wave can be output, thereby the invention overcomes the limitations of the accuracy error verification for the fundamental wave and the harmonic wave of the traditional electronic voltage transformer under the condition of the single frequency; when the accuracies of the fundamental wave and the harmonic wave of the electronic type voltage transformer are verified at the same time under the condition of the periodic non-sinusoidal wave, the requirements of the primary test voltage and the reference are satisfied, so that the non-linear phenomenon of the electronic voltage transformer is verified.

The invention provides a fluorescent bleaching-based super-resolution imaging method. The fluorescent bleaching-based super-resolution imaging method comprises the following steps of 1) marking a sample through fluorescent dye with photo-bleaching characteristics; 2) focusing laser beams onto the marked sample to be tested through a point excitation scanning type laser microscope, wherein the sample to be tested emits fluorescence under laser beam excitation; 3) collecting the fluorescence emitted by the sample to be tested to acquire laser intensity information; 4) scanning the sample point by point through exciting light of certain power at certain scanning parameters so as to directly bleach the sample during the scanning process, to relatively reduce the number of collected effective pixels, to further obtain relatively small fluorescence spots and to directly achieve super-resolution images breaking through optical diffraction limits.

The invention provides a power electronic converter nonlinear identification method based on multi-entropy feature extraction. The method is mainly based on ensemble empirical mode decomposition, Hilbert transform and a least square support vector machine. The method comprises: sequentially solving the power spectrum entropy of the original signal x(t), solving the EMD energy entropy of the effective IMF component R-IMF obtained by screening after EEMD decomposition, and solving the time-frequency information, namely time-frequency spectrum entropy, contained in the original signal after Hilbert transformation is carried out on the R-IMF. The multiple entropies are used as different feature information of the same class to be input into the LS-SVM model, and through training of the model,high accuracy is achieved for recognition of some nonlinear phenomena in the power electronic converter.

The invention discloses a wireless transmission method based on a femtosecond laser and an electric energy transmission device. The flashover discharging between a femtosecond laser transmitter and an electric signal transmitter is collected, the processing is carried out through the wireless transmission technology to obtain stable voltage, which means that the nonlinear phenomenon-filamentation generated by the transmission of a femtosecond laser pulse in the air is used, an electric signal receiving electrode carries out flashover discharging in the femtosecond laser pulse, the voltage pulse of the flashover discharging is filtered and converted into alternating current, and the femtosecond laser pulse is used to carry out far distance wireless power transmission. The peak-peak value of alternating current voltage coupled by a non-contact transformer is reduced to one tenth of the original or even lower, the insulation degree of a back stage circuit can be greatly reduced, and the cost of the back stage circuit is greatly reduced. The output voltage of the invention is direct current voltage which can be used as a power supply by much equipment, and power use requirements in some special conditions such as the wireless transmission of a communication satellite and the power supply of a high speed electric vehicle can be solved.

The present invention provides provide a light power adjusting method, an optical transmitter, and an optical receiver suitable for ensuring high data transmission quality by preventing the rapid increase in SBS which occurs when the light power exceeds a predetermined value.The incident light power with which the SBS-induced backward propagating light included in the reflected light returned from the optical transmission line rapidly increases, i.e., the light power threshold is calculated.By setting the power of the light incident on the optical transmission line at a value equal to or smaller than the thus calculated light power threshold, the rapid increase in the SBS-induced backward propagating light, which is a nonlinear phenomenon of the optical fiber, is prevented.

The invention provides a construction and detection method of a biomolecular motor resonance sensor. According to the invention, in the process of constructing rotary biological sensors, the phenomenon that activation / suppression exists between load and rotation speed is found and nonlinear relationship exists between signal change and load. The nonlinear phenomenon between rotation and load cannot be explained by common theories of mechanics, but can be described by the resonance theory. According to the invention, motor rotary type sensors are developed into resonance type sensors. The regulation and control factors of the sensors of such type are more complicated and the regulation and control requirements are higher; but once resonance conditions are found to develop the application of the sensors to a higher level, larger principle and technology breakthroughs of the biological sensors are obtained; and after the products are put into use, direct economic benefit and huge social benefit can be generated.

The invention discloses a non-inductive chaotic circuit only including two operational amplifiers based on a Wien bridge oscillator. The non-inductive chaotic circuit comprises the Wien bridge oscillator, a capacitor C1, a resistor R and a simplified Chua'sdiode RN, wherein the capacitor C1 is connected to two ends of the simplified Chua's diodein parallel (marked as ends 1 and 1'); the right end of the resistor R is connected to the end 1, the left end of the resistor R is connected to the input end of the Wien bridge oscillator (marked as an end 2), and an output end of the Wien bridge oscillator is connected to an end 2'; and the end 1' and the end 2' are connected to the ground. The non-inductive chaotic circuit adopts a one-level operational amplifier to realize the simplified Chua's diode, so that the simple non-inductive Chua's chaotic circuit only including two operational amplifiers is realized. The provided chaotic circuit can produce complicated nonlinear phenomena, such as periodical limit cycles, chaotic attractors, coexisting attractors, twinning double-scroll chaotic attractors and twinning limit cycles. The non-inductive chaotic circuit becomes a simplest non-inductive Chua's chaotic circuit, and has a larger impelling action on development of the chaotic system.