264 results about "Expansion factor" patented technology

A method of correcting wavefront aberrations of an eye includes determining a high precision conventional intrastromal corneal ablation profile based on a direct removal of the intrastromal corneal tissue. An expanded ablation volume profile is constructed based on the direct tissue removal profile and the expanded tissue volume is to be ablated instead to correct to the wavefront aberrations. The thickness of the ablated profile of a conventional ablation profile is expanded by an expansion factor (Nc-1)/(Nm-Nc), Nc is the index of refraction of the cornea and Nm the index of fill material. An expanded ablation volume filled with the fill material produces the effect of correcting wavefront aberrations as if a much smaller tissue volume were ablated without the fill material.

The invention discloses lead-free glass powder, a preparation method thereof, silver paste containing the glass powder and a crystal silicon solar cell manufactured by using the silver paste. The lead-free glass powder comprises the following components in percentage by weight: 20-30 percent of SiO2, 2-15 percent of B2O3, 40-70 percent of Bi2O3, 1-10 percent of ZnO, 1-10 percent of Al2O3 and 1-5 percent of BaO. The preparation method comprises the following steps of: (1) weighing the components for preparing a mixture; (2) putting the mixture into a crucible for melting; (3) performing water quenching on molten glass; (4) drying; (5) smashing the mixture into powder by planetary ball milling; and (6) screening. The needed silver paste is prepared from the lead-free glass powder, silver powder, an additive and an organic carrier. A solar panel front face electrode and a grid line are manufactured by performing screen printing and sintering on conductive silver paste on a cell substrate, so that the needed solar cell is obtained. The lead-free glass powder has low melting temperature, low softening temperature and low linear expansion factor.

The invention belongs to the communication technology field, relating to a channel coding transmission method based on an unequal mistake protection fountain code. The method comprises the following steps: classifying a signal source according to importance; carrying out virtual expansion on each r layer data according to expansion factor; putting obtained virtual extension layer data into each window; carrying out progressive analysis on the window data with and/or tree algorithm; carrying out LT coding and index replacement according to robustness solitary wave degree; obtaining coding word; carrying out transmission; carrying out decoding. According to the invention, protection of important data is reinforced, simultaneously protection of less important data is not decreased to guarantee to reliable transmission of data.

The invention relates to a preparation method of a carbon-graphite composite material. The preparation method is characterized in that the carbon-graphite composite material is prepared from the following raw materials in percentage by weight: 1.5-2.5% of carbon black, 5%-8% of graphite with the particle size smaller than or equal to 1mm, 25%-30% of calcined petroleum coke powder with the particle size smaller than or equal to 0.075mm, 15%-20% of calcined petroleum coke with the particle size of 1mm-4mm, 10%-15% of electric calcined anthracite with the particle size of 4mm-10mm, 5%-10% of electric calcined anthracite with the particle size of 10mm-16mm, 5%-15% of calcined pitch coke with the particle size of 10mm-16mm, 18%-20% of coal pitch and short carbon fiber, wherein short carbon fiber is equal to 1%-3% of total weight of the raw materials. The carbon-graphite composite material is prepared by the steps of material preparation, mixed kneading, forming, roasting and graphitization and is excellent in performance, high in breaking strength, relatively good in thermal shock resistance and relatively low in expansion factor; the carbon-graphite composite material does not crack and break and has good stability.

A signal processing method divides a first signal of two signals to be compared in similarity into smaller regions, selects one of the regions, and calculates the correlation of the selected one with the other second signal. The method finds a time difference, an expansion factor, and a similarity in one region in which the maximum similarity as the square of the correlation is obtained, and performs integration in the position represented by the time difference and the expansion factor of values based on similarities. The method performs similar processing on all the regions, and evaluates similarity by, in a peak where the integrated value of similarities is a maximum, compares its magnitude with a threshold value. The region corresponding to the peak can be extracted.

The invention discloses a production formula and a manufacturing method of a modified ultra-high molecular weight polyethylene resin. The modified ultra-high molecular weight polyethylene resin comprises an ultra-high molecular weight polyethylene resin, molybdenum disulfide, nano graphite, superfine talcum powder, ethylene bis stearamide, polytetrafluoroethylene and benzoyl peroxide. The modified ultra-high molecular weight polyethylene resin has ultra high wear resistance and favorable temperature tolerance and self-lubricating property. Compared with the resin before the modification, the modified resin has the advantages that the heat distortion temperature is increased by 38 DEG C, the Shore hardness is improved by 20 degrees, the friction factor is decreased by 40%, and the expansion factor is decreased by 30%. The modified resin is widely used for producing products such as gears, valves, artificial joints, skis, oil field transfer pipelines and the like.

The invention discloses a connecting method for sintering/welding titanium-steel dissimilar metal. The differences of physical properties of the titanium and the steel which are dissimilar metal are large, and the titanium and the steel are hard to connect through conventional methods. According to the connecting method, firstly, the titanium or titanium alloy, V-Cu gradient alloy powder C1, C2 and C3 and stainless steel are placed in a die one by one to be pressed in advance, and secondly, the die is placed in a sintering device to be sintered in a spark plasma mode, wherein the V-Cu gradient alloy powder C1, C2 and C3 are composed of mixed powder which is formed by mixing a plurality of kinds of metal powder according to different proportions, and the expansion factor gradient of the V-Cu gradient alloy powder C1, the expansion factor gradient of the V-Cu gradient alloy powder C2 and the expansion factor gradient of the V-Cu gradient alloy powder C3 are matched with one another. The titanium or the titanium alloy and the stainless steel are directly connected and formed at a time in a sintering mode, the method of spark plasma sintering is particularly suitable for sintering molding of V-Cu gradient connectors of the titanium and the stainless steel, and a titanium-steel dissimilar metal sintering/welding connector can have a high mechanical property.

The invention provides a rapid-annealing method for growing large-size sapphire single-crystal with the SAPMAC method. The SAPMAC method is adopted for growing sapphire single-crystal; after growing is finished, the vacuum degree of a crystal growing furnace is kept; electric power source is not cut off; heating power is lowered according to certain temperature reduction procedure until heating power is zero; and then inert gases are led in for rapid cooling. The invention has the beneficial effects that: 1. crystal dislocation density can be lowered, the lattice vacancy of crystal with big diameter and high expansion factor can be lowered, defect concentration such as distortion of lattice, dislocation and the like can be eliminated, crystal cleavage is avoided, and crystal quality and utilization factor can be improved; 2. in-situ annealing of crystal can be realized, crystal growing cycle can be shortened under the precondition of ensuring crystal quality; and 3. production cost can be lowered.

The invention relates to a virtual expansion method of laser television color gamut based on a 1931CIE (Coherent Infrared Energy)-XYZ system. The invention has the advantages that the features of laser large color gamut and high saturation are fully utilized so that the expression color of television images is enriched, the images presented are more graduated and more close to the true color of the nature, and the like. The method comprises the following steps: step 1. performing coordinate transformation under the 1931CIE-RGB system to obtain a coordinate under the CIE1931 color space; step 2. performing laser display matrix transformation; step 3, solving a virtual expansion factor; step 4, expanding equal tone; and step 5, establishing a three-dimensional lookup table to obtain virtual expansion numerical value to be output according to RGB value for inputting television signals by a cube interpolation algorithm method so as to realize virtual expansion finally.

The invention discloses a two-dimensional wake flow numerical simulation method. The method is characterized by comprising the steps that 1, wake flow expansion factors are calculated; 2, based on the step 1, the wake flow air speed under a Park model is calculated; 3, the initial wake flow radius under the Park model is corrected; 4, based on the step 2 and the step 3, the wake flow air speed under the corrected Park model is calculated; 5, based on the step 4, a new wake flow model is set up and named as a Park-Polynomial model; 6, the wake flow air speed under the Park-Polynomial model is calculated. By means of the two-dimensional wake flow numerical simulation method, the air speed of a wake flow zone can be well simulated, the precision is approximately consistent with testing results, the radial distribution better accords with a real flow field, and the advantages of a simple mode, easy encoding, efficient calculation and the like of an engineering model are achieved.

The invention discloses a method for preparing a high-strength water-absorbing expansive polymer plugging agent and belongs to the technical field of preparation of plugging agents. By virtue of a liquid polymer composed of acrylic acid, acrylamide and an acrylonitrile monomer, the acrylamide has high water absorbing capacity of the amide group, so that the water-absorbing expansion rate of the polymer plugging agent is improved; due to the addition of a bisphenol A epoxy resin and a phenolic resin, the bisphenol A epoxy resin and the phenolic resin are modified by using a modified glass fiberflexibilizer, so that the strength and viscosity of the polymer plugging agent are improved; by utilizing modification of sodium fluoride and sodium hydroxide on the bentonite and montmorillonoid inorganic matters, the modified bentonite and montmorillonoid have high expansion factor, and by utilizing sodium persulfate initiation, calcium chloride solidification, cross-linking of the N,N-methylenebis acrylamide and adhesion of polyvinylidene fluoride, the calcium chloride is induced to carry out a cross-linking reaction by the sodium persulfate. Moreover, the plugging agent can absorb water to expand in the reaction process, the strength and water-absorbing expansion rate of the polymer plugging agent are improved, and the polymer plugging agent has wide application prospects.

To judge impacts with a three-dimensional model constituted by a plurality of polygons, rapidly and accurately. The vertex-coordinates of the partial models constituting the three-dimensional model are represented by central-coordinates being the average values of the maximum values and minimum values of respective coordinate components, an expansion factor for achieving prescribed values by multiplication by the differentials between the maximum values and minimum values of each coordinate component, and converted vertex-coordinates obtained by subtracting the central-coordinates from the respective vertex-coordinates and then multiplying by the expansion factor; the central-coordinates and the expansion factor being stored as floating-point values, and the converted vertex-coordinates being stored as integers (ST3). Moreover, a judgement subject partial model, being a partial model of the partial models constituting the three-dimensional model to which impact judgement is to be applied, is selected (ST1), and impact judgement is performed with respect to this judgement subject partial model (ST7-ST11).

The invention discloses an RBF (Radial Basis Function) neural network-based coal and gas outburst prediction method. The method comprises the steps of 1, performing dimensionality reduction on feature data of coal and gas outburst, and performing normalization processing on the feature data subjected to the dimensionality reduction to obtain normalized feature data; 2, clustering the normalized feature data by using a K-mean algorithm and calculating the center of an RBF; 3, training an RBF neural network on the normalized feature data, and introducing an optimal expansion factor and an optimal weight when the number of neurons in a hidden layer is determined by an adaptive differential evolution algorithm; 4, increasing the number of the neurons in the hidden layer, and repeating the steps 2-3 to obtain global optimal parameters of the RBF neural network, thereby determining a prediction model of the RBF neural network; and 5, predicting test data by using the prediction model of the RBF neural network. According to the method, the optimal parameter adaptive problem of the RBF neural network can be solved, so that the coal and gas outburst can be quickly and accurately predicted.

This invention relates to receiver combined with equilibrium and integration technique, which comprises the following parts: equilibrium receiver to receive the expansion factors activated and to process the interference signals through equilibrium technique; integration test receiver to receive the data expansion factors activated and process the multiple-address interference between signals though integration technique; selector to selectively output; controller to activate the said receiver and test receiver according to senior expansion factors and to control the output of the receivers.