70results about How to "Strong theoretical foundation" patented technology

The invention relates to a thin-walled component arc wire filling additive manufacturing temperature field predicting method. The method includes the steps that a stacking condition of a thin-walled component is determined; a thermal cycle curve is measured; the shape of any stacking layer molten pool above a second stacking layer is observed; a model is built and grids are divided; a heat dissipation boundary condition and a heat source parameter are loaded; a model temperature field is calculated, a thermal cycle parameter is extracted, the length of the stacking layer molten pools is measured, and compared with test data, the maximum error of thermal cycles and size errors of the molten pools are all smaller than preset values through a fine-tuning heat source model shape parameter; the fine-tuning model shape parameter is loaded in a numerical model of the thin-walled component, and arc wire filling additive manufacturing temperature field predicting is completed. The numerical calculation method is adopted, by comparing the thermal cycle parameters on a substrate with the sizes of the molten pools of the stacking layers, thin-walled component arc wire filling additive manufacturing temperature field predicting is accurately completed, and a theoretical basis is provided for solving residual stress and deformation problems caused in the thin-walled component arc wire filling additive manufacturing process.

The invention provides a minimum miscible phase pressure computing method of low-permeability reservoir CO2 flooding. The minimum miscible phase pressure computing method of low-permeability reservoirCO2 flooding comprises the following steps that minimum miscible phase pressure and underlying parameters of four or more samples are obtained by adopting a slim-tube displacement experimental method; the underlying parameters of the four or more samples are substituted through a theoretical formula method to calculate and obtain the minimum miscible phase pressure ; the minimum miscible phase pressure error of a same sample is obtained by comparing the slim-tube displacement experimental method and the theoretical formula method, and empirical constants are obtained by substituting the underlying parameters of four selected samples into a logarithm formula and establishing an augmented matrix; and a computational formula model is obtained by fitting the minimum miscible phase pressure ina low permeability reservoir and the underlying parameters. According to the minimum miscible phase pressure computing method of the low-permeability reservoir CO2 flooding, the minimum miscible pressure determined by the slim-tube displacement experimental method is more accurate, the theoretical formula method is more convenient and fast, and the cost is lower; at the same time, calculation requirements of the low-permeability reservoir in the Northern Jiangsu Basin can be met, a new derivation computational formula is more accurate in computational accuracy, the theoretical basis is higher, the labor intensity is low, and the minimum miscible pressure computing method of the low-permeability reservoir CO2 flooding is suitable for the use of low-permeability reservoir in the Northern Jiangsu Basin.

The invention discloses a power system vibration mode matching method based on a matrix perturbation theory. The method comprises the following steps: first, calculating to obtain a characteristic value and a characteristic vector corresponding to an initial system mode before parameter change by applying characteristic value analysis, and then calculating approximate values corresponding to the system mode of the characteristic value and the characteristic vector after the parameters change by utilizing the matrix perturbation theory; then, determining the corresponding relationship between the approximate values of the characteristic value and the characteristic vector before and after the parameters change; later on, finding a mode which is closest to the approximate values from exact values of the system mode after the parameters change, establishing the corresponding relationship between the exact values and the approximate values of the system mode after the parameters change; finally, establishing the matching and corresponding relationship between the system modes before and after the parameters change according to a contact link between the system modes after and before the approximate values of the system modes serving as parameters change. The method has the beneficial effects that the principle is simple and clear, the discrimination is fine and the criteria are complete.

The invention provides a design method for an output feedback controller with a time varying sampling period. The method comprises the steps of setting time delay of a network control system to be a constant value and to be less than a sampling period, wherein a time varying sampling period is bounded, packet loss meets a Bernoulli random sequence and the probability is known; discretizing an original linear time invariant network control system and obtaining a discrete time varying system with uncertain items through conversion; obtaining the maximum singular value of a matrix and a conjugate transpose matrix through solving to obtain parameters in the discrete time varying system; according to state variables received by a controller and the obtained parameters in the discrete time varying system, building a dynamic output feedback controller; combining the built linear matrix inequality and the Lyapunov stability principle, solving the matrix in the feedback controller to determine and obtain a dynamic output feedback controller. The method takes into consideration the instability of sampling periods of network control systems, has the advantages of clear design thought, high stability and simple operation and can be applied to engineering practices.

The invention discloses a method for solving a text similarity based on the Gini index. The method comprises the following steps: performing text word segmentation processing by use of the word segmentation technology, matching with a stop word list to perform a stop word elimination operation on a vocabulary, and obtaining a series of vocabulary positions and word characteristic weighted values according to the research statistics; collecting and reducing dimensions of the text vocabulary by use of a target weight function as shown in description, combining the vocabularies with high similarity according to the semantic similarity, collecting and reducing the dimensions of above characteristic words again, and solving the inter-textual similarity by use of the similarity between the vectors. Compared with the traditional text characteristic vocabulary extracting method, the method disclosed by the invention is higher in accuracy, better in application vale, and good in data processing effect; the defects of an information gain method are overcome, the result is more suitable for the experience value, the text characteristic vocabulary high-dimensional spare problem and the problem of the synonyms and polyseme are solved, the contribute degrees of different vocabularies to the text thought are computed, and the good theory basis is provided for the subsequent text similarity and text clustering.

The present invention relates to a fuzzy system reliability design method in combination with a modal interval algorithm. The method comprises the following steps of: 1. defining operations of fuzzy numbers; 2. judging multiple events and carrying out derivation on the multiple events and the sub-events of the multiple events; 3. judging whether the monotonicity of the multiple events is consistent with the monotonicity of the sub-events of the multiple events, and separately performing modal interval analysis by using coercive optimal and partial coercive optimal theories; 4. performing calculation according to a modal interval operation rule; 5. performing calculation to obtain an interval reliability index, security possibility degree and invalidation possibility degree of a system for reliability design of the system; 6. determining whether the reliability design of the system is performed in a serial, parallel or serial-parallel manner, and if so, performing the next step, or otherwise, ending; 7. performing modal interval analysis in the same method as the steps 2 to 4 so as to obtain the accurate security possibility degree and invalidation possibility degree of the system; and 8. determining the design reliability of the fuzzy system according to an actual requirement. According to the method, the correctness of the system reliability design is improved and the calculation amount is reduced.

The invention discloses a wind power plant equivalent value modeling method based on a main ingredient analysis method and a layered clustering algorithm. The method comprises the following steps of extracting 13 complete state variables for expressing the operation state of a wind power unit according to a built mathematical model of a built doubly feed induction generator; on the basis of a mainingredient analysis method, extracting a primary variable expressing the main oscillation features of the state variable in 13 station variables; using the primary variable as a grouping index; usinga layered cluster algorithm for performing clustering grouping on the wind power plant of the doubly feed induction generator; according to the result of the primary variable clustering, dividing thewind power plant into a plurality of machine unit groups; on the basis of the division result, building a wind power plant equivalent value model. The calculation complexity is low; the realization is easy; the application range is wider; the practical requirements of dynamic equivalent value analysis of the wind power plant can be well met; good theoretical basis is provided for analysis of theelectric power system safety and stability after the wind power integration.

The invention discloses a kit capable of rapidly and specifically detecting mycobacterium tuberculosis infection, and comprises three pairs of specific primers for detecting free small RNA of mycobacterium tuberculosis. Specific primers are designed for detecting free small RNA of mycobacterium tuberculosis, and free small RNA is extracted from human peripheral blood, detected, and synthesized so as to obtain cDNA. Then a realtime quantitative amplification system containing gradient-diluted cDNA, and a kit and method for rapidly and specifically detecting mycobacterium tuberculosis infection are established. The kit and method solve the problems that in the prior art the diagnosis time in a lab for patients is too long, the detection sensitivity is low, and the operation is very complicated. The provided kit is capable of being used to detect mycobacterium tuberculosis in a clinical lab, and can also be used to evaluate clinical treatment effect. The provided kit has the advantages of high sensitivity, good specificity, low cost, and convenient operation on detecting mycobacterium tuberculosis, and is capable of fully filling the requirements on rapid diagnosis in clinic or lab.

The invention provides an improved text similarity solution method. The method comprises the following steps: performing word segmentation and unused word removal processing on two texts (the formula is as shown in the specification), calculating weights of feature vocabularies in the texts based on an information theory method, calculating position weights of the vocabularies according to the position information of the vocabularies, constructing feature value target functions (the formula is as shown in the specification) in the texts by integrating all factors, extracting two feature vocabulary vectors, and converting a text similarity problem into a vector distance problem. Compared with the traditional text similarity calculation method, the improved text similarity solution method provided by the invention has the advantages of higher accuracy and wider application range, and meanwhile provides good theoretical basis for subsequent text clustering.

The invention discloses a preliminary prospecting well optimum decision-making method and system. The preliminary prospecting well optimum decision-making method comprises the steps: calculating the success probability of a preliminary prospecting well; calculating the value of the preliminary prospecting well; and establishing a decision coordinate system, and judging whether the preliminary prospecting well is an optimal preliminary prospecting well or not according to the positions of the data points of the preliminary prospecting well success probability and the preliminary prospecting well value in the decision coordinate system. According to the preliminary prospecting well optimum decision-making method, on the basis of considering the success probability and the value of the preliminary prospecting well, the two-dimensional optimization model is utilized to carry out preliminary prospecting well optimization decision, and a reliable and rapid decision basis can be provided forthe preliminary prospecting well, so that the deployment quality of the preliminary prospecting well is improved, and the exploration investment is inclined to a region with good benefits.

The invention provides a cell nucleus fluorescent dye as well as a dyeing method and application thereof, and provides a novel fluorescent dye for cell nucleus dyeing. The cell nucleus fluorescent dye has good membrane permeability, high sensitivity, rapid nucleus dyeing efficiency, good light stability, good biocompatibility and longer-wavelength exciting light and emission light, and can be applied to fluorescent dyeing of cell nucleuses.

The invention relates to an unfrozen water model based on adsorption and capillary coupling effect, which is prepared by the following steps: (1) collecting a soil sample, measuring the specific surface area AS of the soil and the humidity at room temperature, and taking the humidity of the soil at room temperature as the initial water content w0; (2) establishing an unfrozen water content model, and calculating the unfrozen water content wu; the method has the advantages of simple expression, few input parameters, convenience in calculation and deeper theoretical basis.