603results about How to "Method science" patented technology

The invention relates to a method for calculating the tracing contribution of a sudden accidental water pollution source at a point source, which is effective in rapid tracing of a river basin and environmental management and protection of the river basin. The method includes: according to the natural geographical features of the river basin, determining the control area corresponding to the control section of the river basin; using the monitoring data of the pollution source and the statistical data of the pollution source to budget regarding the pollution source in the river basin; using a one-dimensional unsteady water quality model to establish the relationship between pollution source and water quality of the section; using the relationship between pollution source and water quality of the section to calculate the contribution coefficient of the pollution source within the river basin and characterizing the contribution of pollution sources. The method is novel and unique, easy tooperate and use, accurate in calculation, and high in efficiency, makes full use of the basic information of the existing pollution source, quickly feeds back the state of the pollution source in theriver control section in a short time, locks the pollution source which has relatively greater contribution to the river water quality in the river basin, provides the support for the pollution tracing of the river basin, and is effectively used for the environmental protection and treatment of the river.

The invention discloses an air conditioner for automatically adjusting the air quality and an adjusting method thereof. The air conditioner comprises an indoor air quality sensor, an outdoor air quality sensor, an indoor humidity sensor, an outdoor humidity sensor, an indoor dust sensor, an outdoor dust sensor, an indoor temperature sensor, an outdoor temperature sensor and a ventilating device, wherein the ventilating device is at least provided with a PG motor. In addition, the air conditioner also comprises an air quality control module, a humidity control module, a temperature control module and a ventilating control module, wherein the air quality control module is used for comparing indoor air quality data with outdoor air quality data and for generating and outputting a ventilating signal or a non-ventilating signal; the humidity control module is used for comparing indoor humidity data with outdoor humidity data and for generating and outputting a ventilating signal or a non-ventilating signal; the temperature control module is used for comparing indoor temperature data with outdoor temperature data and for generating and outputting a ventilating signal or a non-ventilating signal; and the ventilating control module is used for starting the PG motor to ventilate under the conditions of simultaneously meeting all the ventilating signals and for turning the PG motor off under the condition of meeting part of the ventilating signals. The invention automatically dehumidifies, humidifies and controls the ventilating amount and has a scientific air quality improving method.

The invention discloses a gravity inductive type axis-counting device and a method for detecting the state of a tract district thereof, relating to a railway transport management device and a management method thereof. The gravity inductive type axis-counting device comprises an axis detector, an axis-counting information processing system, an input-output subsystem and a power supply, wherein the axis detector is composed of a wheel electronic detector and a gravity inductive type sensor unit; the wheel electronic detector consists of an axis-counting CPU unit, a signal processing unit, a sensor power unit and a state detecting unit; the axis-counting information processing unit comprises a CPU unit, a communication unit, and an I / O unit; and the input-output subsystem consists of a dynamic drive assembly unit, a relay and a button. In the method, a wheel signal is detected by a gravity inductive type sensor arranged on a rail, and is transmitted to the wheel electronic detector and the axis-counting information processing unit for processing, thus judging the state of the tract district. The invention has the advantages of accurate detection result, high reliability, scientific method and capability of realizing automatic judgment on the idle and occupied states of the tract district.

An on-line monitoring method for the changing circulatation gap of the steam turbine is disclosed that comprises the steps: acquiring data, calculating the flux of the main steam, correcting parameters of the regenerative system, correcting the primary parameter and the end parameter, designing the parameter fitting in operating mode and diagnosing the augment of circulating gap. The main steam flux of the steam turbine can be obtained by computer from the main steam temperature and pressure of the main steam, the regenerative steam temperature and pressure, the vacuum condenser, the temperature and pressure in each of the regenerative exhaust points, the water temperature of the ports, the drain temperature and the water flux of condensate, the flux value of the cooling water of the superheater and the reheater when the steam turbine is running. Based on the heat balance diagram in the operating mode of the steam turbine, the temperature, pressure and the internal efficiency ratio of the regenerative ports in the condition of the main steam are contrasted with the real temperature, pressure and the internal efficiency ratio of the regenerative ports to realize the on-line monitoring for the changing circulatation gap of the steam turbine. The method is scientific to realize the automatical on-line monitoring and exact fault diagnosis.

The invention relates to a high temperature creep life accelerated test method of a material, which comprises: a plurality of groups of short time stress relaxation tests of the material at the same temperature, acquiring a relaxation rate-stress curve based on the numerical differentiation principle, forming a relaxation creep rate-stress curve by utilizing a relaxation equation, calculating creep data to build a creep curve, and building a steady state creep rate curve and a Norton creep equation. The method starts from the physical relation between relaxation and creep, covers rather broad properties of creep strain rate by utilizing the short time relaxation process, and educes broader creep data than that educed from general creep tests by above ten times, thereby effectively reducing the amount of high temperature creep tests and time of tests and providing basic data for development of new material and engineering application.

The invention aims to provide a partition definition computing method for the river environmental flow of an artificially interfered area without hydrological data, and can effectively solve the computing problem of the river environmental flow of the artificially interfered area without hydrological data. On the premise of river water ecology function, the composition of environmental flow is defined, then the average runoff volume and annual distribution of the river in the area without hydrological data are studied by utilizing a hydrologic analogy method and a parameter contour line method; according to the flow data on this basis, the environmental flow of different partitions is computed, and the environmental flow of different nodes of the river is determined. The method is novel, unique and scientific, and is an environmental flow computing method based on functional requirements; and water resource optimization and deploying and water conservancy project ecology scheduling can be carried out on the rivers which are greatly affected by artificial interference degree and lack of hydrological data, so that the minimum environmental flow required for normally developing river functions is guaranteed, the river ecological system is repaired, the river ecological environment is protected, and the economic and social benefits are great.

A vector geographic space data watermarking-method based on integer wavelet transform includes fetching original vector geographic space data from mapping databank, enciphering watermark information with chaos sequence, carrying out integer wavelet transform on coordinate string of said geographic space data and embedding watermark information into low frequency coefficient of wavelet transform; picking up watermark information by comparing wavelet coefficient mutual relation of data string to be tested to original reference data string when watermark is required to be picked up.

The invention relates to an apparatus and method for measuring elastic turbulence characteristics of a viscoelastic polymer in a porous medium, wherein a side connector of a fluorescent microscope of the apparatus is connected to a CCD (couple charged device) camera, a saline container, a polymer solution container and a synthetic oil container that are connected with an oil / water container are parallelly connected between an inlet of a micro metering pump and an inlet of a two-dimensional mesh microscopic simulation model, the two-dimensional mesh microscopic simulation model is provided with an inlet pressure sensor and an outlet pressure sensor, and a light guide arm of a micro field particle image speed-measuring system is positioned right above the two-dimensional mesh microscopic simulation model; all the micro field particle image speed-measuring system, the fluorescent microscope, the inlet pressure sensor and the outlet pressure sensor are connected to a data graphic data station. The apparatus and method are capable of effectively recognizing elastic turbulence of viscoelastic polymer solution in porous medium seepage, and providing qualitative and quantitative description for elastic turbulence characteristics.

The invention relates to an online monitoring method for fouling degree of a flow passage of a steam turbine, which is characterized by comprising the links of data acquisition, main steam flow calculation, back-heating system parameter correction and diagnosis of the fouling degree of the flow passage, and comprising the following steps of: for each middle group, comparing the front and back pressure ratio of each group obtained by online monitoring with the front and back pressure ratio of each group when the flow passage is in a normal state by using the current back-heating extraction pressure measuring point of each level in the running of the steam turbine through the links so as to judge the fouling state of the flow passage of each middle group of the steam turbine; for the final group, comparing the pressure before the final group obtained by online monitoring with the pressure before the final group of the steam turbine under the condition of the same main steam flow so as to judge the fouling condition of the flow passage area of the final group of the steam turbine and realize the online diagnosis of the fouling degree of the whole flow passage of the steam turbine. The invention has the advantage of scientific method, and can realize automatic online monitoring and accurate judgment, and the like.

The invention relates to a method for effectively screening self-discharging batteries. The method comprises the following steps: (1) determining low-voltage-state voltage knee points of batteries by using a trickle charge method; (2) carrying out charging and discharging on the batteries, allowing the voltage of the batteries to be finally located at the low-voltage-state voltage knee points, and after the voltage of the batteries tends to be stable, measuring and recording the voltage OCV1 of each battery; (3) storing the batteries at a set temperature for a period of time and measuring and recording the voltage OCV2 of each battery; and (4) calculating the voltage drop value delta V of each battery, wherein delta V satisfies the equation that delta V = OCV1 - OCV2, and if the voltage drop value delta V of a battery exceeds a set value, the battery is a self-discharging battery need to be screened out. The method provided by the invention is more scientific, accords with principles, can more accurately screen out self-discharging lithium ion batteries and reduces irreversible capacity loss of batteries in the phase of screening of self-discharge; thus, excellent electrochemical performance and safety performance of batteries in subsequent usage are guaranteed.

The invention discloses a real-time online diagnosis method of a coupling parallel misalignment fault, belongs to the fields of mechanical vibration state monitoring and fault diagnosis, and relates to the real-time online monitoring of the vibration state of the large steam turbine generator set. The method comprises the following steps: acquiring vibration signals of shafts on two sides of a coupling of the steam turbine generator set and temperature data of bearing bushes of bearing pedestals on two sides of the coupling; judging in real time whether the temperature of the bearing bushes of the bearing pedestals on the two sides of the coupling of the set is abnormal, and combining the Fast Fourier Transform (FFT) spectrum analysis method to perform shaft speed frequency vibration phase condition verification on the relative vibration data of the shafts on the two sides of the coupling; and automatically diagnosing in real time whether the coupling parallel misalignment fault occurs in the set based on real-time quantitative computation and analysis and in conjunction with various verification results in an online manner. The method has the advantages of scientificness, reliable conclusion, automatic realization of the real-time online monitoring and the fault diagnosis and the like.

The invention discloses a method for preparing metal magnesium by using dolomite as a raw material, and aims to solve the problems of low reducing efficiency, high energy consumption, long production period and serious pollution existing in the conventional method for preparing the metal magnesium. The method comprises the steps: crushing of dolomites, vacuum low-temperature light calcining and recycling of carbon dioxide, cooling and heat recovery, ball-milling of mixed materials, briquetting of mixed materials, vacuum high-temperature hot reduction, separation of magnesium blocks, and utilization of slag, wherein in the vacuum low-temperature light calcining, the crushed dolomites undergo light calcining in a continuous type vacuum calcining furnace for 1 to 3 hours at the calcining temperature of between 500 and 1,000 DEG C and under the furnace pressure of 10,000 to 60,000Pa, MgCO3 and CaCO3 in the dolomites are decomposed in sequence, the reaction expression is: CaMg(CO3)2=CaCO3+MgO+CO2(gas) and CaCO3=CaO+CO2(gas), and the mixture of carbon dioxide and magnesium oxide and calcium oxide is obtained; and the carbon dioxide which flows in the furnace and heats the dolomites is recycled.

The invention discloses a method for obtaining a load density index based on cellular historical data. The method for obtaining the load density index based on the cellular historical data is characterized by comprising the following steps: a cellular is generated, the power supply area of a 10KV feeder line serves as class cellulars, and the class cellulars contain actual measurement data; the power supply area is divided according to square meshes of the same size to form the class cellulars, and a load is to be forecasted. An electric power geographic information system (GIS) is set up, historical loads, power supply areas and land information of the class cellulars are integrated in the GIS, the cooperation index of the load density is determined, the maximum value of the load density of the class cellulars serves as a benchmark, and the load densities of other similar cellulars are normalized. The classified load densities over the years are obtained, a relation equation between the cellular load and the classified load densities is set up, and the load density is obtained through the least square method. A spatial load is forecasted, the size of the spatial load in a target year is forecasted according to the obtained index of the classified load densities, and the load value of each class cellular is further worked out.

The invention discloses a multi-objective power flow optimization method of a VSC-HVDC (voltage source converter-high voltage direct current) containing alternating-current / direct-current system, which is characterized by comprising the following steps: establishing a model, selecting to-be-optimized variables and optimization objectives, and determining constraint conditions; setting an initial variable, and giving a to-be-optimized variable range; under the condition of taking the to-be-optimized variables as population individuals in the optimization process, in a hybrid encoding mode, randomly generating an initial population according to the to-be-optimized variable range; calculating the power flow of the alternating-current / direct-current system by using an alternate iterating algorithm; getting the corresponding optimization objective function value of each individual in the population; carrying out rapid non-dominated sorting on the individuals in the population, calculating a virtual fitness, and through selection, crossing and variation processing, generating sub-populations; retaining excellent individuals in parent individuals by using an elitist strategy; judging whether algorithm termination conditions are satisfied, if so, turning to a step 9), and completing optimization; otherwise, turning to the step 4); completing the optimization process, and outputting results. The method has the advantages of scientificity, strong applicability, good effect, and the like.

The invention discloses a college entrance examination voluntary artificial intelligence filling system, which is composed of the following parts: automatic data collector EADH, college entrance examination big data knowledge base CDKB, deep convolutional neural network perception component DCNA, deep convolutional neural network weight component, deep volume Productive neural network analysis component DCNS, fast Monte Carlo search tree optimization MROP, college entrance examination strategy optimization model CSOM, college entrance examination volunteer form automatic generator AFAG, user operation interface, background management module, university and professional information query module, score line and enrollment plan query modules, simulated reporting and accurate reporting modules, user voluntary evaluation modules, college and professional intelligent recommendation modules, occupational employment recommendation voluntary modules, user characteristic evaluation modules, and college entrance examination policy news and enrollment dynamic modules. Intelligent technology is used to assist the decision-making function of college entrance examination volunteers.

The invention discloses a method for controlling the synchronous degradation of each layer of a co-extrusion composite film by utilizing the same biological base. Aiming at the co-extrusion composite film which is in three layers or more than three layers, a biological active additive 'EcoPure' is used as the biological base. The method is characterized by comprising the following steps of: calculating a weight proportion relationship between carbon contents of each layer of the co-extrusion composite film first, then determining the addition concentration of the biological base of each layer according to the weight proportion relationship between the carbon contents of each layer in extruded polymer of each layer before the preparation, and making the degradation rate of each layer of the co-extrusion composite film be accordant. The method disclosed by the invention has the contribution of having a predictable control ability for the biological degradation process and the degradation rate of multi-layer co-extrusion composite film which is composed of different polymers; and by balancing the concentration of the biological base, the biological degradation rate which is suitable for the final processing environment is provided, and the appearance, the function and the physical and mechanism performance of a product before being discarded are ensured to be unchanged.

The invention provides an urban traffic abnormality identification method based on a complex network theory. The method comprises the following steps: step 1, constructing an urban traffic network based on traffic data; step 2, carrying out feature extraction and screening based on a complex network theory; step 3, carrying out the abnormality recognition and prediction of a traffic system; and step 4, evaluating and verifying a model. According to the invention, the scientific and reliable technical support and theoretical support can be provided for the recognition and prediction of the urban traffic congestion abnormality based on the complex network theory and a machine learning method. Therefore, the congestion abnormality of the urban traffic system can be efficiently and accuratelyidentified and predicted, and the method has important significance in ensuring the healthy and stable operation of the urban traffic system and improving the reliability of the urban traffic system;and the method is scientific and good in manufacturability and has the great application and popularization value.

The invention relates to a crack splicing method in bridge quality detection. The machine vision technology, modern sensing technology, data analysis processing technology, calculation technology canbe effectively fused into bridge quality detection. Aiming at the acquired local image of the crack; the splicing of crack images is accurately completed. The automatic detection of the whole crack ofthe bridge is met; the safe use of the bridge is ensured. Method of installing an installation device, Collecting crack images, Crack image stitching, carrying out graying on the spliced image; grayscale transformation and image filtering preprocessing are carried out. The method is scientific. The bridge crack automatic splicing device is simple in structure, easy to operate, good in detectioneffect and capable of rapidly and accurately achieving automatic splicing of the same crack at different visual angles, the problem that long cracks cannot be contained in crack images is solved, themaximum crack width and the automatic detection level of the real position of the maximum crack width in bridge quality detection are further improved, and smoothness and safety of traffic transportation are effectively guaranteed.

The invention discloses a flow-excitation failure real-time diagnosis method used for a large-scale steam-turbine generator unit, belonging to the vibration-state real-time on-line automatic detection for the large-scale steam-turbine generator unit in the mechanical vibration-state detection and failure diagnosis field. The failure diagnosis method comprises the sections of data collection, data preprocessing, low-frequency vibration condition verification, unit load condition verification and failure diagnosis and the like. Whether the unit suffers the flow-excitation failure is diagnosed according to the results of low-frequency vibration condition verification and unit load condition verification. The method has the advantages that the diagnosis is reliable; and the automatic real-time on-line detection and failure diagnosis can be realized and the like.

The invention relates to a multi-energy complementary coordinated power generation scheduling method based on a wind-light-water-fire storage combined system, which is characterized by comprising thefollowing steps of firstly, simulating a time sequence for producing the wind power / photovoltaic output by utilizing an improved Markov chain method; secondly, determining load requirements, minimum economic output of a thermal power generating unit and boundary conditions of forced output of a hydraulic power plant, and calculating a renewable energy power generation operation feasible region; then, preferentially arranging wind power and photovoltaic power generation in the renewable energy power generation operation feasible region, and formulating a water and electricity dispatching strategy on the basis of the wind power and photovoltaic power generation; and finally, comprehensively considering the operation cost of the thermal power generating unit and the energy storage operation cost considering life loss; formulating a thermal power generating unit and energy storage combined dispatching strategy with the minimum total operation cost of the thermal power generating unit and energy storage in the dispatching period as the target, solving a corresponding optimization objective function through a particle swarm algorithm, and then obtaining the wind-light-water-heat-storagecombined system dispatching strategy. The method has the advantages of scientificity, reasonableness, simplicity, applicability and the like.

The invention discloses a method for producing fermented fish paste. The method for producing the fermented fish paste mainly comprises the steps of low-value fish raw materials, pretreatment (removal of scales, head, tails, internal organs and vertebras), soaking in salt vinegar water, draining, soaking in ozone water, draining, defibrination, salt addition, in-jar fermentation, seasoning, mixedhomogeneity and obtaining of finished products. The method adopts a salt vinegar water soaking method to remove fishy-smell substance, is scientific, easy to operate and good in effect. The salt vinegar water is used for soaking fish slices, and acetic acid promotes solubility of the fishy-smell substance (trimethylamine oxide and dimethylamine oxide) in water with the assist of the salt water and enables the fishy-smell substance to be solved in the water, thereby achieving the removal purpose. Ozone solution produced by an electrolysis type ozone generator is used for soaking and disinfection, sundry fungus pollution and usage of preservatives are reduced, and the requirement for green production is met. Self enzyme of fishes is utilized to perform natural fermentation, thereby ensuringgood taste and special flavor of the fish paste.

The invention discloses a preparation method of natto red yeast rice health care food for assisting in lowering blood lipid. The preparation method is characterized in that soybeans serves as the raw material and is soaked, steamed and boiled, cooled, inoculated with bacillus natto, fermented, refrigerated, frozen, dried, crushed and processed into natto powder, then red yeast rice extract and magnesium stearate are added, then the ingredients are mixed to be prepared into granules or capsules, and the natto red yeast rice health care food is prepared from, by weight, 50-70% of the natto powder, 30-50 parts of the red yeast rice extract and 0-3% of magnesium stearate. According to the preparation method, adopted raw material components are scientific in compatibility, the adopted technological process and method are reasonable, scientific and easy to operate, the obtained product is free of toxic and side effects, capable of being easily absorbed by a human body and convenient to eat, it is beneficial to prevent and control atherosclerosis hardening of the arteries and lower the risk of cardiovascular diseases, and the health care function of assisting in lowering blood lipid is achieved.

The invention relates to a production method for extracting oryzanol from rice bran oil niger. The method can effectively solves the problem of the industrialized extraction of the oryzanol from the rice bran oil niger to meet the market requirements. The method adopts a technical proposal that the method comprises the following steps: heating up and dissolving the rice bran oil niger rich in the oryzanol, then diluting the rice bran oil niger through methanol, then saponifying the rice bran oil niger by complementing alkali, carrying out the alkaline bath filtration to obtain the filtrate of saponification liquor, filtrating the filtrate of the saponification liquor through acid pickling, carrying out water washing, acid dipping, purification, granulation and drying, so as to obtain the oryzanol. The method is scientific and advanced, and can effectively solve the technical problem of the industrialized extraction of the oryzanol from the rice bran oil niger. The oryzanol has the high quality; and the method has the high production efficiency and can effectively meet the market requirements on the oryzanol. The method is a great innovation for the oryzanol production and has great economic and social benefits.

The invention relates to a distribution network frame planning method for conducting clustering and partitioning on the basis of load points and considering geographical factors. The method is characterized by comprising the steps that a clustering algorithm is improved through load weighting factors, the load points in service areas of all transformer substations in a to-be-planned area are clustered and partitioned, and the points with the smallest distance with the transformer substations in the partitions serve as source load points; a connection relation matrix capable of representing theupstream and downstream relationship of the load points is built according to power flow, the matrix is used for rapidly getting current of a circuit and judging the influence of the position of a tie line on faulty line downstream load transaction supply; by means of an improved minimum spanning tree algorithm, the main network frame planning scheme with the minimum annual investment, running and geographic barrier cost is obtained; in order to further improve the reliability of the scheme, tie line planning among the partitions is conducted by taking the minimum investment and power outagecost as the target, and different power outage cost calculation methods are adopted for different load transaction supply situations. The method is scientific, reasonable, simple and practical.

The present invention relates to a method for demodulating reference Chirp ultra- wideband system group based on active frequency spectrum compression code which can solve problems of serious ultra-wideband wireless transfers multi-path interference, difficult miniaturisation, poor coexisting performance and low communication distance. The method includes steps as follows: generating a waited-module baseband signal, information bit transmitted in code element period for processing data mould, data by-pass road in code element period and orthogonal code word in reference by-pass processing orthogonal code moulding in data by-pass road and reference by-pass road, processing coalition to the signal in data by-pass and reference by pass with addition, then multiplicating, moulding the multiplicated signal for generating transmitted signal, and transmitting by antennae, processing oblique pulse compressing under condition of gauss white noise, demoulding orthogonal code to the signal, processing multiplication demoulding orthogonal code for the signal compressed by active frequency spectrum with orthogonal code, and processing information judgement to the result. The method is advancedand scientific which can solve efficient communication problem in middle remote distance ultra- wideband system.

The invention discloses a method for source modification treatment of fluoro-gypsum which comprises the steps of, (1) raw material selection, charging composite active triggering agent and alkaline material into the fluoro-gypsum, wherein the mass fraction of each components are, fluoro-gypsum 93-97, composite active triggering agent 1-2, alkaline material 2-5, (2) agitating and mixing, transferring to rainproof yard, stewing, (3) stacking, trickling and maintaining. The modified fluoro-gypsum is applied to cement production.

The invention discloses a student poverty state prediction method based on data excavation. The method comprises: obtaining learning data of all students at school, consumption data information, and proportion of poor students and non-poor students; dividing student data information into a training set and a test set, and proportion of poor students and non-poor students in each set is consistent with a determined proportion; using an oversampling algorithm to perform data balance on the data in the training set; using a random forest algorithm to perform model training on the training set, testing and evaluating the model by the test set, to obtain a student poor state prediction model in optimal performance; and using the student poor state prediction model to predict the poor state of the students. The method performs comprehensive examination and prediction on poor state of the students through objective data and behaviors of the students at school, so as to prevent subjectivity and randomness in student poor state evaluation. The method is scientific and practical, and can rapidly perform algorithm solution and data analysis.

The invention discloses a technology for preventing and treating coal seam roof water damage through dynamic pressure maintaining grouting blocking fissures of horizontal long drill holes in a miningfractured zone, and relates to the technical field of stope face safety of coal mines with roof water damage. At present, domestic roof water damage prevention and control technologies mainly comprisegoaf filling, strip mining, thickness-limited mining, drainage, static grouting and the like, and great limitations exist in deep water-rich extra-thick coal seam mining, such as waste of a large number of resources, high cost and unsatisfactory water control effect. According to hydrogeology of a mining area and development characteristics of the height of a mining overlying strata water diversion fractured zone under specific mining conditions, a reasonable target layer is selected, the horizontal long drill holes are formed, slurry meeting the requirements of the technology is selected, and along with mining of a working face, the horizontal long drill holes in the mining fractured zone dynamically block fissures in a pressure maintaining mode to prevent and treat coal seam roof waterdamage.

The invention discloses a method used for simulating an all air-air conditioning system and a device thereof. The method used for simulating the all air-air conditioning system comprises the steps that a fresh air temperature / humidity value and a return air temperature / humidity value are received; according to the fresh air temperature / humidity value and the return air temperature / humidity value, a fresh air enthalpy value and a return air enthalpy value are obtained by calculating respectively; when an absolute value of a difference value between the fresh air enthalpy value and the return air enthalpy value is larger than a preset difference value, a working mode which is a working mode with the smallest fresh air capacity of the all air-air conditioning system is obtained. The method used for simulating the all air-air conditioning system and the device thereof serve as an all air-air conditioning system teaching experiment method which is totally based on a simulation system and a device thereof, the size is small, the energy consumption is low, the failure rate is low, and teaching is convenient.

The invention relates to a computing method for double-fed wind power unit overspeed off-grid critical time. The computing method is characterized in that the method is started with setting up an electromechanical transient mathematic model after a DFIG is disturbed, the effects on the electromechanical transient of the factors such as the initial operation conditions, disturbance intensity and Crowbar protection motions of the DFIG are analyzed, the conditions reaching overspeed protection motions of a DFIG unit are deduced, and a wind power unit off-grid living example in a certain wind power field is analyzed through the provided method, and the wind power unit with the overspeed protection motions is correctly recognized according to the calculated time from acceleration to overspeed protection motion fixed values of rotors of all units. The computing method has the advantages of being simple and rapid in computing, high in evaluation accuracy and application value, wide in on-line application prospect and the like.