159 results about "Scattering process" patented technology

A distributed fiber optic sensor simultaneously interrogates the sensing fiber with two counter propagating light beams. One beam is set to a constant frequency. The second beam is modified to contain a “comb” of frequencies, with each frequency component in the comb offset by a predetermined amount. Each of the frequency components in the comb, herein referred to as teeth, is able to interact with the counter-propagating beam through the Brillouin scattering process. With proper selection of the comb characteristics such as the number of teeth, the frequency spacing of teeth, the spectral width of teeth, and the relative amplitude of the teeth, a representation of the Brillouin spectrum at each point in the fiber can be obtained simultaneously with a single pass through the fiber.

A pulsed cascaded Raman laser (10) includes a pulsed light source (102) for generating a pulsed light (104) having an optical spectrum centered at a source wavelength. A non-linear Raman conversion fiber (106) is coupled to the pulsed light source (102). The pulsed light (104) traverses the nonlinear Raman conversion fiber (106) and the source power at the source wavelength is converted to a power output of an output signal (108) having an output wavelength longer than the source wavelength by a cascaded Stimulated Raman Scattering process, such that most of the source power is converted to the power of the last Stokes order in a single pass through the non-linear Raman conversion fiber (106).

A virtual grid imaging method capable of eliminating scattered radiation effect and an imaging system thereof are provided. The method is mainly applicable for imaging with high energy rays, in which scattered rays reaching a surface of a detector are not filtered, and data of the scattered rays and straight rays are all sampled, and then, separation and inhibition of scattered ray component are performed for the sampled data, thereby eliminating the scattered ray component in the resulted image. The method particularly includes the following steps: (1) decomposing a digital image into multi-band images from high to low according to frequencies; (2) performing de-scattering process for low-frequency band images; (3) performing contrast enhancement process for high-frequency band images; and (4) merging the images of various frequency bands processed in the step (2) and the step (3), and forming an output image. Experiment shows that, in digital X-ray imaging, the present invention can obviously eliminate the scattered radiation effect, and meanwhile significantly reduce the dosage of the rays, in which only one third of the required dosage of a common grid is used to obtain the same image brightness.

Device for measuring the distribution of strain and / or temperature along an optical fibre through the analysis of the stimulated Brillouin scattering, characterized by the fact that both the “optical pump” light from which the scattered energy is derived, and the “stimulus” or “probe” light that stimulates the scattering process are both derived by the same ring-type tuneable optical circuit that at the same type amplifies the amplitude of the “optical pump” light and generates, through a controlled Brillouin amplified scattering, the “probe” light having the spectrum linewidth required for the measurement needs and a wavelength shift with respect to the “optical pump” light that is accurately and quickly tuneable and fully adjustable within the range that is needed for interrogating a distributed optical fibre sensor.

A distributed fiber optic sensor simultaneously interrogates the sensing fiber with two counter propagating light beams. One beam is set to a constant frequency. The second beam is modified to contain a “comb” of frequencies, with each frequency component in the comb offset by a predetermined amount. Each of the frequency components in the comb, herein referred to as teeth, is able to interact with the counter-propagating beam through the Brillouin scattering process. With proper selection of the comb characteristics such as the number of teeth, the frequency spacing of teeth, the spectral width of teeth, and the relative amplitude of the teeth, a representation of the Brillouin spectrum at each point in the fiber can be obtained simultaneously with a single pass through the fiber.

A pulsed cascaded Raman laser (10) includes a pulsed light source (102) for generating a pulsed light (104) having an optical spectrum centered at a source wavelength. A non-linear Raman conversion fiber (106) is coupled to the pulsed light source (102). The pulsed light (104) traverses the nonlinear Raman conversion fiber (106) and the source power at the source wavelength is converted to a power output of an output signal (108) having an output wavelength longer than the source wavelength by a cascaded Stimulated Raman Scattering process, such that most of the source power is converted to the power of the last Stokes order in a single pass through the non-linear Raman conversion fiber (106).

The invention belongs to the field of radar communication technology and discloses a calibration method for a polarization synthetic-aperture radar. The method comprises the steps of acquiring the echoed data of the fully polarimetric scattering process; establishing a polarization calibration model for the polarization synthetic-aperture radar; calculating the unbalanced parameters of a cross polarization channel in the polarization calibration model and the crosstalk parameters of a polarization channel; according to the unbalanced parameters of the cross polarization channel and the crosstalk parameters of the polarization channel, preliminarily correcting the echoed data of the fully polarimetric scattering process to obtain preliminarily corrected echoed data; calculating the unbalanced parameters of a receiving channel, correcting the preliminarily corrected echoed data for a second time according to the unbalanced parameters of the receiving channel, and finally obtaining the calibration data of the full-polarization synthetic-aperture radar. According to the method, the parameter estimation performance is still ensured to be excellent on the premise that the noise powers of cross channels are not consistent and the signal to noise ratio is low.

The invention discloses an eco-friendly soil-restoration processing device for greening of a municipal garden. The device comprises an outer box body. The bottom of the outer box body is equipped witha driving mechanism. One side of the outer box body is equipped with a support rack. One side of the support rack is provided with a soil shoveling board. The interior of the support rack is equippedwith a transport mechanism. The upper end of the outer box body is provided with a pressuring pump and a stirring motor. The end part of the pressuring pump is equipped with a pressuring pipe. The bottom in the outer box body is provided with a material scattering mechanism and a drum. The interior of the drum is equipped with a stirring shaft. The interior of the drum is provided with a filter net. A material poking scraping plate and stirring blades are installed on the stirring shaft. The eco-friendly soil-restoration processing device for greening of the municipal garden has the followingbeneficial effects: through the driving mechanism, automatic movement of the device is achieved; automatic collection of soil is realized through the soil shoveling board and the transport mechanism;the device is used for orderly filtering, spraying medicine and stirring; the device has a compact structure and suitable for construction of the municipal garden; and the material scattering mechanism is used for scattering processed soil on the ground so that soil is kept smooth and flat and convenient for subsequent application.

Speckle effect in imaging applications is reduced by generating additional speckle patterns on the screen such that the speckle patterns are overlapped and the overlapped speckle patterns average out on the screen to appear as a noise background to the viewers. The speckle patterns are generated by discrete optical signals of a visible frequency comb. A visible frequency comb having discrete optical signals is generated through modulation-instability processes, phase-conjugation processes, and Bragg-scattering processes using a non-linear optical material and a wavelength converter.

A gaming machine includes a liquid crystal display 27 having a liquid crystal panel 173 and a light guiding plate 174 placed at the rear of the liquid crystal panel 173 for guiding light emitted from illumination light means 176a, 176b for the liquid crystal panel 173 into the liquid crystal panel 173, and a variable display device placed at the rear of the liquid crystal display 27 and having a plurality of reels 3L, 3C, and 3R provided in a row each on which a plurality of symbols are arranged. Parts of the light guiding plate 174 to which the reels 3L, 3C, and 3R are opposed are cut out or are formed with recesses on the reel side and light scattering process is applied on end faces 174a, 174b, and 174c of the cutouts or the recesses.

An air duct, in particular for a motor vehicle heating, ventilating and / or air conditioning system, which is acoustically optimized by virtue of the fact that at least one cross-sectional discontinuity is constructed by making use of a phenomena which occur as acoustic scattering processes at the cross-sectional discontinuity. The cross-sectional discontinuity should extend substantially perpendicular to the flow direction in the air duct.

Photonic signals are tagged with a pre-selected modification, such as a polarization signature to carry data across an obstructed path between sender and receiver. Communication authentication through polarization variation allows for Yuen-Kumar or entangled photon quantum communication protocols to propagate through environmental scattering media such as air, smoke, fog, rain, and water. While ultraviolet light photons are well suited as a carrier for quantum communication signals scattered in air, it is appreciated that visible wavelengths have longer propagation paths in water to convey non-line-of-sight data. A secure signal is scattered by the media and simultaneously communicated to a single recipient or multiple recipients exposed to scattered signal portions. A process of solving the scattering processes through a random scattering media is provided to reconstruct a quantum keyed message at a receiver. The scattering of the signal is utilized herein to provide non-line-of-sight and intentional short-range communication.

The invention discloses a near-infrared spectral tomography reconstruction method based on a neural network and belongs to the field of medical image processing. In a Boltzmann radiation transmissionequation, a light transmission process is regarded as an absorption and scattering process of photons in a medium, the interaction between light and tissue is determined by absorption coefficients, scattering coefficients and phase functions of reactive scattering distribution, only particle properties of the light are considered in transmission, and the volatility of the light is not considered;therefore, phenomena of polarization and interference correlated with the volatility of the light are not considered, and only the energy transmission of the light is tracked. The reconstruction method based on the BP neural network is used for reconstructing the distribution of the absorption coefficients of the light, and a reconstruction result of the distribution of the absorption coefficientscan be obtained through calculation. By means of the method, not only can the distribution of the absorption coefficients be accurately reconstructed, but also high computational efficiency is achieved.

Disclosed is a terahertz parameter source on the basis of potassium titanium oxide arsenate crystals. The terahertz parameter source comprises a laser pumping system, a terahertz parametric device and a cooling system, wherein the terahertz parametric device comprises the potassium titanium oxide arsenate crystals, pumped laser emitted by the laser pumping system illuminates along the terahertz parametric device, and the terahertz parameter source is formed by scattering process of stimulated excitons of the potassium titanium oxide arsenate crystals. The output frequency range of terahertz waves is from 3.5THz to 6.5THz. The terahertz parametric device further comprises a rear cavity mirror and an output mirror, and the laser pumping system emits the laser sequentially along the rear cavity mirror of the terahertz parametric device, the potassium titanium oxide arsenate crystals and the output mirror of the terahertz parametric device. According to the terahertz parameter source and the application thereof on the basis of the potassium titanium oxide arsenate crystals, nonlinear crystals of potassium titanium oxide arsenate are used, the nonlinearity gain of the crystals is high, meanwhile, high damage threshold is achieved, and tunable terahertz radiation waves in the frequency range from 3.5THz to 6.5THz can be obtained through an angle tuning mode.

The invention relates to a continuous variable light and atom ensemble entanglement production device and mainly aims at solving the technical problem of existing probable production of separated variable light and atom ensemble entanglement. According to the technical scheme, the continuous variable light and atom ensemble entanglement production device comprises a light source unit, a plurality of light beam coupling systems, an atom system and a measurement system. The light source unit is provided with a pump light pulse signal aP output end, a writing light pulse signal aW output end, a reading light pulse signal aR output end, an output end for two local oscillation light signals aL1 and aL2 and an output end for two simulation light pulse signals aL3 and aL4. The device utilizes orthogonal components of light fields in continuous variable quantum information and collective spin waves of atom ensembles to definitely produce Stokes light and atom ensemble entanglement through spontaneous Raman scattering process and conducts measurement and analysis on the light and atom ensemble entanglement through anti-Stokes light produced in the spontaneous Raman scattering process.

The invention discloses method and device for correcting scattering of a digital X-ray image, and aims at improving the accuracy of correction of the scattering of the images. The method comprises the steps of determining image quality evaluation quality, die body information, exposure conditions and a scattering model; simulating the image scattering process of the scattering model according to the exposure condition and the die body information; calculating or measuring to obtain the initial value of key parameters of the scattering module; adjusting key parameters within the disturbance range of the initial value of each key parameter; selecting the key parameter which enables the optimal image quality evaluation index as the optimal key parameter of the scattering model under the image quality evaluation index, the exposure condition and the die body information.

The invention discloses adhesive interlining machining equipment which sequentially comprises a powder scattering device, a powder blowing and sucking device and a powder material output device, wherein the powder scattering device comprises a first rack, a first cloth guide roller mounted on the first rack, a material discharge assembly, a material hopper, a powder collection mechanism, an operation platform and partition doors; the powder blowing and sucking device comprises a second rack, a transmission mechanism mounted on the second rack, two group of oppositely-arranged blowing and sucking air blowers, and an impact roller; and the powder material output device comprises a third rack, a material feeding assembly and a material discharge assembly. The adhesive interlining machining equipment provided by the invention is provided with the powder scattering device, the powder blowing and sucking device, and the powder material output device, so that the uniformity of powder scattering can be improved, the consumption amount of hot-melting adhesive powder can be reduced; residual scattered hot-melting adhesive powder is recycled and reused in a powder scattering process, so that the use rate of the hot-melting adhesive powder is improved; and furthermore, the adhesive interlining machining equipment is simple and convenient to operate, and the personnel risk coefficient of workers in an operation process can be reduced to the lowest extent.

The invention relates to a method for remodeling medium objects by electromagnetic inverse scattering. The method comprises following steps: utilizing Maxwell's equations and constitutive equations to deduce forward and reverse integral equations for electromagnetic scattering; guessing the shape of an object to be detected and discretizing integral equations with a method in order to obtain matrix equations; utilizing a Gauss-Newton minimization method to regularize ill-conditioned equations during the reverse scattering process following discretization, wherein used regularized parameters are obtained by a multiplicative regularization method; and adopting a born iterative method to carry out iteration and obtaining wave number of detected mediums at the needed precision in order to achieve the objective of remodeling mediums.The method helps to avoid the problem in the conventional method that parameters are obtained by a lot of experiment data so that solving efficiency is increased.

The present invention provides an antenna directional pattern-based method for correcting the RCS of a calculation target. The imaging-based near-field and far-field transformation method is adopted as a basis, and the microwave imaging concept is introduced to establish the relationship among the two-dimensional image, the near-field echo and the scattering characteristics of a target. The accurate extrapolation of near-field data is realized without the need of imaging during the treatment process. Since the influence of an antenna directional pattern is considered during the echo scattering process of the near-field echo of a single station, the data representation of a target near-field is more accurate. An approximate antenna directional pattern function, instead of an actual antenna directional pattern function, is adopted. During the extrapolation process, the influence of the antenna directional pattern is corrected. Therefore, the construction complexity of the directional pattern function is simplified. Meanwhile, the calculation error of the target RCS is reduced.

The invention discloses a laser source device of coherent anti-Stokes Raman scattering microscopic system, which comprises: an ultrashort pulse fiber laser for providing the pumping light of a parametric amplifier and the Stokes light required by the process of coherent anti-Stokes Raman scattering process; a tunable continuous light semiconductor laser and a fiber amplifier for amplifying the output light of the tunable continuous light semiconductor laser, wherein the light amplified is regarded as the seed light of the parametric amplifier; a light beam combiner for spatially combing the pumping light and the seed light of the parametric amplifier; a first nonlinear crystal and a second nonlinear crystal for sequentially receiving the light beams from the light beam combiner, wherein the two nonlinear crystals are respectively regarded as the parametric amplifier and the frequency multiplier for the seed light; a collimating focusing device arranged between the first nonlinear crystal and the second nonlinear crystal and a collimating device arranged behind the second nonlinear crystal; and a low-pass filter arranged behind the collimating device and used for filtering out the pumping light and the Stokes light required by the process of coherent anti-Stokes Raman scattering.

The invention discloses a method for preparing an electrostatic dry impregnated fiber felt, which comprises the following main steps: (1) two kinds of different fiber yarns are chopped, blended, and settled for mesh paving to form a fluffy and evenly-blended blank felt; (2) resin powder is scattered on the surface of the blank felt according to the mixture ratio; (3) the blank felt is subjected to dry impregnation under the action of an electric field through an impregnating machine; (4) an interface and the bottom of the blank felt are paved with non-woven fabrics, and the double-sided needling is performed for reinforcement; and (5) the felt is formed through edge cutting and rolling. The method has the advantages that the method overcomes the technical defects existing in the prior powder scattering process, realizes the even impregnation of the resin powder to the fiber felt, has small investment and low energy consumption, does not use solvents and adhesives, relates to broad industry products, is suitable for industrialized production, is more scientific and reasonable compared with the prior chopped strand felt preparation technology, and provides a novel process route for manufacturing thermoplastic reinforced fiber felts.

The invention relates to a manufacturing process for chemically plating a NiP-Cu electrode on the partial surface of a ceramic element, in particular to a process for manufacturing an electrode by a chemical deposition method for base metal copper or nickel. The process comprises the following steps of: preparing the ceramic element, cleaning, drying, roughening, printing, activating, soaking, preplating, plating copper, dehydrating, drying, performing heat treatment, welding, testing and the like. The invention has the advantages that: a base metal layer on the surface of the ceramic element has high adhesion force and high performance and is easy to weld; the partial surface is chemically plated, so that the process is simple, and adhering, abrading and scattering processes of the conventional full electrode chemical plating process are eliminated; raw materials are saved, and the cost is reduced to one fifth of the original cost; and a plating solution formula is perfected, so that mass production of the electrode which is chemically plated on the partial surface of the ceramic element can be realized. The process is suitable for manufacturing electrodes of all ceramic elements.

The invention discloses a stimulated Raman scattering (SRS) compensation method in a distributed optical fiber temperature sensor system. The method comprises the following steps of: (1) at specific pumping light power and specific optical fiber length (L), calculating the backward transmission light intensity after the optical power of a forward transmitted self-emitted Raman scattering signal is subjected to Rayleigh scattering at the L and the backward transmission light intensity after the pumping light is subjected to forward transmission and Rayleigh scattering at the L; (2) calculatinga stimulated scattering process by using the numerical value of a RungeKutta method to obtain SRS signal light; (3) acquiring a self-emitted Raman scattering signal and an SRS signal at a random point z of an optical fiber according to the step (2); (4) acquiring the magnification of the self-emitted Raman scattering signal due to stimulation; and (5) acquiring a real Raman scattering signal according to the magnification. By the method, the influence of SRS can be eliminated, and the precision of temperature measurement is improved.

The invention relates to a generating device for entanglement of continuous variable atom ensemble and belongs to the generating device for the entanglement of atom ensemble applied to a quantum information network. The generating device is used for solving the technical problem that probability preparation exists in the present preparation for the entanglement of atom ensemble of variables separation. According to the technical scheme provided by the invention, the generating device for entanglement of continuous variable atom ensemble comprises a light source unit, a plurality of beam coupling systems, two sets of atom ensembles, an entanglement measuring system and a feedback unit. The orthogonal component of a light field in the continuous variable quantum information and the collective spin wave of the atom ensemble are utilized to generate the entanglement of two sets of stokes light and spin wave of atom ensemble in a spontaneous raman scattering process, and then interference signals of the two beams of stokes light are fed back to a first atom ensemble through the quantum entanglement exchange, the entanglements of the first atom ensemble and the second atom ensemble are certainly prepared, and the generated stokes light is utilized to measure and analyze the entanglement of the atom ensemble.

The invention discloses a calculation method for path losses during a single scattering process in non-line-of-sight ultraviolet communication. The method comprises: step one, parameters of a transmitting terminal and a receiving terminal are set, an area V' and a public scattering body V are defined, and a range of the V' is solved; step 2, the area V' is divided into a plurality of micro elements and coordinates of the micro elements are obtained in a spherical coordinate frame; step three, traversal of the area V'is carried out and the area V' is segmented into a plurality of micro elements V'', whether the micro elements V'' are in the public scattering body V is determined, and if so, the energy that is scattered by the micro elements V'' and then is received by Rx is calculated and is added, and calculation is carried out to obtain the total energy received by the Rx, so that a path loss value is solved. According to the provided calculation method, the simulation time is short; the path loss of the communication system is calculated easily; and the fitting with a simulation result of an MC method is high.

An air duct, in particular for a motor vehicle heating, ventilating and / or air conditioning system, which is acoustically optimized by virtue of the fact that at least one cross-sectional discontinuity is constructed by making use of a phenomena which occur as acoustic scattering processes at the cross-sectional discontinuity. The cross-sectional discontinuity should extend substantially perpendicular to the flow direction in the air duct.

The invention discloses a product multi-information fusion identification failure remedying method based on the D-S evidence theory. The technical problem that tracking disconnection is caused by an existing method in the production process of individual products is solved. According to the technical scheme, the method comprises the steps that multi-source information correlation and data structure existing in the product physical and manufacturing process is analyzed, a product scattering and incomplete multi-source information model needed in the scattering process is built, the feature data of failure identification parts and product historical database similarity measure are calculated through a class-center-based Euclidean distance and improved variable coefficient weighting method, fusion identification is carried out on a feature layer through the D-S evidence theory, the identifications of the failure products are effectively recovered and remedied, and then the technical problem that tracking disconnection is caused in the production process of the individual products due to DM code failure is solved. Experimental results show that the identification accuracy of preventing tracking failure is larger than 95%, efficiency is high, recovering and remedying are reliable, and practicability is good.

The invention discloses a sand rain device capable of automatically controlling the drop distance and an application method of the device. The sand rain device comprises a sand hopper, a sand falling device, a model box and an automatic lifting pedestal; the drop distance is controlled accurately in a manner that the weight of scattered sand is converted into the sinking height of the pedestal. The invention also discloses an application method of the sand rain device capable of automatically controlling the drop distance. The application method of the sand rain device capable of automatically controlling the drop distance comprises the following technical steps: determining the density of a sand sample, determining the drop distance, fixing the model box on the pedestal which can automatically adjust the sinking height by virtue of the weight, horizontally moving the sand hopper and scattering the sand, wherein the pedestal automatically sinks according to the weight of the sand sample until the sand scattering is finished. The vertical height of the sand falling device does not need to be moved in the sand scattering process, and the sinking amount of the pedestal is always the same with the height of the sand sample, namely the drop distance is constant all the time. The sand rain device capable of automatically controlling the drop distance overcomes the defects that the sand sample is nonuniform and the density is inaccurate as the drop distance can not be accurately controlled in the conventional sand rain sample prepartion process and has the advantages of high accuracy, convenience in operation, simple and feasible technology, high practicability and the like.