191results about How to "Solve engineering problems" patented technology

The invention discloses a numerical simulation method for cavitation compressible flow shock wave dynamics and belongs to the field of numerical simulation of cavitation compressible flow and shock wave dynamics. A three-dimensional computing watershed based on three-dimensional geometric modeling software is established; a three-dimensional computing watershed mesh is divided based on mesh generation software; a cavitation compressible flow computational fluid dynamics model is established; an initial boundary condition is set to perform a three-dimensional computational domain flow field numerical computation; based on flow field post-processing software, the computational result is post-processed to obtain the unsteady evolution process of a multi-phase bubble structure. The numerical simulation method for cavitation compressible flow shock wave dynamics in the invention facilitates in-depth study of the cavitation physical mechanism, can be applied to the field of cavitation compressible flow and shock dynamics numerical simulation and solves related engineering problems. The cavitation compressible flow and shock dynamics numerical simulation engineering application area comprises hydraulic machinery, marine propellers, aviation turbo pump induction wheels, underwater supercavitation weapon applications.

The invention discloses an error model predictive control method based on kinematics modeling of omnidirectional mobile robots. The error model predictive control method comprises the following stepsthat S11, a velocity constraint kinematics model is established between FM-OMR four Mecanum wheels; S12, a tracking error kinematics model of a FM-OMR is established; S13, aiming at the trajectory tracking problem of the FM-OMR and the tracking error kinematics model, an error model predictive controller combined with a velocity constraint equation is designed; and S14, according to the error model predictive controller, effective trajectory tracking parameters between the omnidirectional mobile robots are controlled so as to enable tracking errors between the omnidirectional mobile robots toremain unchanged. According to the error model predictive control method based on the kinematics modeling of the omnidirectional mobile robots, the error model predictive control method based on the trajectory tracking error kinematics modeling is provided aiming at the omnidirectional mobile robots with the four Mecanum wheels, the non-holonomic constraint problem of the effective trajectory tracking control is solved, and the accuracy and the validity are realized.

The invention discloses a signal synchronization method used for UWB high-precision positioning system. The method comprises the following steps that: (a) a signal synchronization platform is established, wherein the signal synchronization platform comprises a synchronization controller and N base stations used for UWN high-precision positioning, the synchronization controller is connected with a receiving end of the first base station through a wired transmission medium, and the base stations are successively cascaded; (b) the base stations successively receive and forward a clock synchronization signal emitted by a synchronization signal generation device of the synchronization controller and respectively reset high-precision timing clocks of the base stations; (c) after each base station receives a UWB positioning information code, the clock number of the high-precision timing clock of each base station at the moment is recorded, and the time delay value between any two base stations is obtained; and (d) the time delay value is used as a correction value and is added to the time information of the corresponding base station, and the synchronous timing of the base stations is realized. By adopting the above method, the precise signal synchronization among the base stations is realized.

The invention discloses a preparation device of random oriented multi-set joints rock bridge samples. The preparation device comprises I-shaped guide rails, a dead plate, L-shaped supports, angle control devices and insert devices. The lower part of the preparation device is composed of two parallelly-arranged pairs of I-shaped guide rails and rod pieces. A square formed by the I-shaped guide rails and the rod pieces has the same inner diameter as a sample box. The L-shaped supports are nested in the I-shaped guide rails. The angle control devices are fixed on the L-shaped supports. The insert devices are fixed on the angle control devices through fastening screws. Thus, all the above components together form a basic structure of the device. In comparison with the prior art, the invention has the following advantages: the device is practical and simple, and can manufacture multi-sets of joints; manufactured samples can be used in direct shear tests and true triaxial tests; and the device is convenient to use, has high precision and high practicability, and is adopted to achieve objectives of really stimulating joints, enhancing work efficiency, reducing experimental errors, optimizing test results and solving practical engineering problems.

The invention belongs to the field of environment protection, and in particular relates to an optimization design method of an anaerobic continuous flow agitator bath type biological hydrogen production reactor. The method comprises the following steps: researching reactor internal flow field characteristics of different types of stirring paddles under the conditions of different paddle-bath diameter ratios and different agitating speeds and influence on hydrogen production process, by using a numerical simulation software based on computational fluid mechanics technology; obtaining detailed flow field information, such as velocity field, turbulence energy and dissipation rate thereof, biogas integration rate and shearing rate distribution by adopting a two-phase flow model, and analyzing and comparing different flow field information obtained through simulation according to influence on hydrogen production process by the various flow field information, thereby determining an optimal stirring paddle style and agitating speed combination, and providing an effective method for the optimization design of the agitator bath reactor. The optimization design method of the anaerobic continuous flow agitator bath biological hydrogen production reactor is mature in technology, avoids the blindness of hydraulic design of the reactor using an empirical or semiempirical association method, and has the advantages of being visual in optimization cycle effect and short in optimization cycle, saving cost, and the like.

The invention relates to a preparation method of a C / C (carbon / carbon) composite material slider for a pantograph, and belongs to the technical field of preparation of materials for electric locomotives. The preparation method comprises the following steps of: according to the weight ratio of carbon cloth and carbon felt of (7.5-9): (3-1), circularly overlapping single layer 0-degree weft-free carbon cloth, carbon fiber web tire, 90-degree weft-free carbon cloth and carbon fiber web tire sequentially, and introducing carbon fiber bundles in the direction vertical to the spread by a relay type acupuncture method to form a 2.5D carbon fiber acupuncture integrated felt with density of 0.3-0.6g / cm<3>; performing high-temperature pre-treatment at 1500-2100 degrees centigrade, and performing chemical vapor deposition pyrolytic carbon treatment until obtaining the C / C composite material with the density of 1.4-1.6g / cm<3>; machining according to predetermined size, performing polymer dipping-carbonizing treatment and graphitization treatment sequentially, and then machining according to designed size, so as to obtain a product. The process is simple, a product has excellent mechanical and electrical properties, and the industrial application is prompted.

The invention discloses a particle-reinforced composite-material finite-element modeling method of considering a microstructure interface, relates to a composite-material finite-element modeling method, and belongs to the field of particle-reinforced composite materials. According to the method, a deviation method is used to establish a geometric model of the reinforced-phase particle interface onthe basis of definition of traditional particle-reinforced composite-material finite-element models on geometric modeling, materials and contact of a matrix and reinforced-phase particles, consideration of influences of the microstructure interface on a particle-reinforced composite-material finite-element model is realized through carrying out assignment of material and contact attributes to thereinforced-phase particle interface, accuracy and reliability of particle-reinforced composite-material finite-element model simulation are improved, and then engineering problems of the particle-reinforced composite-material field are solved. In addition, the method has the advantage of simplifying complexity of digital image processing and finite-element software modeling. The method is suitable for, but not limited to, finite-element modeling of particle-reinforced composite materials.

The invention relates to a distribution network communication networking mode based on an EPON (Ethernet Passive Optical Network) layering technology in distribution network optical fiber communication networking and an application thereof, belonging to the technical field of distribution network intellectualization in the power industry. A communication convergence layer is formed between a backbone communication layer local side node and a converting station node, and comprises a communication convergence switch (or a regional Ethernet switch); abundant optical fiber cores subjected to uplink convergence from a converting station to a local side backbone communication network are connected with a power distribution communication core router of the local side node; the power distribution communication core router is connected with a power distribution automatic main station system; and a downlink passes through the converting station node, and enters a communication access layer by using an EPON layer. The problem of contradiction between different communication service applications and maintenance of a main electric network and a distribution network is solved. Backbone communication optical fiber core resources are fully utilized, the optical transmission equipment resources of a communication network are not occupied, the reliability of a network communication backbone layer of the distribution network is enhanced, independent networking is performed, convenience is brought to maintenance, and the distribution network communication networking mode has the advantages of very high expandability and the like.

The invention provides an air compression system and a control method. The air compression system comprises air compressors, a detection assembly, a valve assembly, a function switching module and a controller. At least one of the air compressors is provided with a frequency converter. The detection assembly is used for detecting the gas parameters in an outlet pipeline. The valve assembly is connected between an air suction valve and an oil-gas separator and used for forming the internal air circulation of the air compressors, lowering the pressure difference of inlets and outlets of the air compressors and reducing the start and unloading torque. The function switching module is used for changing the electric drive mode of the air compressors so that the air compressors can be switched between the power frequency and the variable frequency. The controller is used for calculating and adjusting the output frequency of the frequency converters according to the detected parameter changes for adjusting gas supply. The system solves the pressure of the maximum efficiency within the required pressure range and assigns the value to a PID so as to control the air compressors to act; when the air compressors operate, the loading and unloading pressure value is set, and the start and stop of the frequency converters are controlled; and the dew point temperature is calculated, a drying machine is started and stopped automatically, the optimum operation of energy efficiency is achieved, the work efficiency is improved, and the operation cost is lowered.

The invention discloses a freezing reinforcement simulation test method suitable for shield ground butt joint. According to the method, a first shield tunneling machine model and a second shield tunneling machine model are arranged, and the method comprises the following steps of: (1) excavating a frozen earth test box underground; (2) respectively arranging a plurality of freezing pipes on shells of the two shield tunneling machine models; (3) respectively arranging a plurality of strain rosettes on the inner surfaces and the outer surfaces of the shells of the two shield tunneling machine models; (4) respectively welding at least one reinforcing steel bar on the shells of the two shield tunneling machine models, and arranging a soil mass pressure box and a temperature sensor on the reinforcing steel bar; (5) filling soil into the frozen earth test box, and carrying out soil consolidation; (6) connecting all the freezing pipes into a freezing pipeline by a freezing device; and (7) starting to freeze and acquiring and analyzing the data. The freezing reinforcement simulation test method is suitable for the freezing method construction simulation test of the shield ground butt joint, can be used for simulating the process of shield ground butt joint freezing method construction, and saves fund, manpower and time compared with the test using physical prototype.

The invention discloses a layer stranded optical cable, which is suitable for being used under extreme climatic conditions such as high cold weather, high hot weather, high temperature difference weather, etc., and has relatively small cross sectional area. The technical proposal is that the layer stranded optical cable comprises a cable core and a protective cover surrounding the cable core, wherein the cable core is twisted by at least two optic cable core wires, which are prepared by wrapping optical fiber with a metal sleeve. The invention replaces the non-metal sleeve in the prior art with the metal sleeve, so that the optic cable core wire has higher side pressure resistant performance, the sleeve of the optical fiber cable is not armored by the steel strip or aluminum strip at the inner side or outer side thereof, the center of the optical fiber cable has no need to bear heavy reinforced core, and the outside diameter of the optical fiber is remarkably reduced. Furthermore, because of the relatively low expansion coefficient of the metal sleeve, the invention solves the engineering problem arising from relatively severe thermal expansion and contraction of common loose tube layer stranded optical cable in regions with high cold weather, high hot weather or high temperature difference weather.

The invention relates to a calibrating method of a control-point-free camera measurement system in the field of view in camera measurement. The calibrating method comprises the following steps of: linking a video camera and a total station fixedly together; establishing a coordinate system of the total station by taking a measurement site as an origin of a coordinate, and calibrating the internal and external parameters of the coordinate system of the total station of the video camera at a place with control point labels; then transferring a fixed linked body of the video camera and the total station to a measurement position to be installed fixedly, and dotting and measuring the corresponding relationship between the coordinate system of the total station at the state and a measurement coordinate system by utilizing the total station; and finally converting the internal and external parameters of the video camera into the measurement coordinate system, so that the internal and external parameters of the video camera under the measurement coordinate system are calibrated for subsequent measurement. The method can be used for separating the calibrating position and the measurement position, can be used for calibrating the video camera of multiple special conditions of sea, air and the like, and widens the application range of the calibrating method.

The invention discloses a dynamic shock-absorbing and dissipating energy device of reducing high tower structure wind vibration response, which comprises the following parts: steel pendulum tie1 whose one end hangs on the structure6, another end hangs with mass block2; the block2 can be used for boring iron shot or casting aluminum steel ball; the pendulum tie1 crosses the hole; the antifatigue damage device is installed in suspension construction; the pendulum tie1 crosses cylindrical compression spring31, whose both extremities of perforated bearing plate32 are clamped by fastener33; the upper, lower end of pendulum tie on mass block2 install antifatigue damage device3; the periphery of mass block is fixed with bump amortization dissipating energy component rubber ring4 whose amortization is more than 5%; There is a protection and repair suspender5 between structure6 and mass block. The control structure is effective, simple and reliable, which is installed in the mast cartridge for vibration damping control the mast structure shacking; the invention improves the control effect, which avoids the big and complicated device.

The invention discloses a power transmission tower tower-leg auxiliary material topological-structure optimization method based on an improved artificial fish swarm algorithm. The method comprises the following steps: 1) firstly establishing a tower leg auxiliary material optimization mathematical model taking the fact that the quality of a tower leg is lightest as a target function, and satisfying a constraint condition through adding a penalty term to the target function, 2) loading a corresponding parameter group for determining a tower leg design scheme to artificial fishes, and achieving a change of the design scheme through a change of a swimming position of each artificial fish, 3) searching optimized artificial fish individuals through adoption of an artificial fish swarm algorithm, and 4) when an end condition is satisfied, outputting the optimal artificial fish individual, converting the optimal artificial fish position parameter into a corresponding structural parameter of the tower leg design scheme, and finally outputting the tower leg design scheme. The method can process a topological configuration change problem of a tower leg auxiliary material of a power transmission tower, and also improve structural optimization efficiency and precision through visual field and a foraging behavior.

The invention discloses a while-drilling detection method of lithological components of a tunnel roof, which is applicable to the technical field of mine tunnel supporting. While-drilling rock fragments in a roof punching process of a roof bolter are collected through a special rock fragment collection device, and a whole process of rock fragment drainage, filtering, precipitation and drying is finished on a tunnel driving working surface; an enhanced handheld type ore analyzer is combined to determine the lithological components of the tunnel roof in a certain range instantly. The while-drilling detection method provided by the invention is simple to operate and convenient to test; a punching procedure in an anchor bolt supporting process is realized and detection analysis on lithological characters of the tunnel roof is finished at the same time; the while-drilling detection method is particularly suitable for geological conditions that the lithological characters of mines are complicated and diversified; the difficult problem of quantitatively describing the lithological components of the roof is solved and scientific evidences can be provided for designing and adjusting a tunnel roof supporting manner and supporting parameters.

The invention relates to an inversion method of the atmospheric refractivity profile. The method comprises the steps that an atmospheric layer is layered; beacon laser is emitted; air sounding equipment vertically ascends to the sounding height of each atmospheric sub layer; the deflection angle of a reflector when the reflector in the air sounding equipment intercepts and captures the beacon laser and returns the beacon laser to a laser receiver, and the received light intensity is maximum is measured; the geocentric angle of the reflector in each atmospheric sub layer and the incidence angle of the beacon laser in each atmospheric sub layer are calculated; the total refraction angle of each atmospheric sub layer and the gradient of the atmospheric refractivity along with the height change are calculated; a drawing is made by using the height as the X axis, the atmospheric refractivity as the Y axis, the atmospheric refractivity of each atmospheric sub layer as a starting point and the gradient of the atmospheric refractivity along with the height change as the slope at each section; the atmospheric refractivity profile is obtained. The inversion method disclosed by the method has the advantages that the atmospheric refractivity profile can be reversed in real time on the spot; technical support and theoretical support are provided for laser application to various engineering fields of satellite high-precision orbit determination, space high-precision measurement and the like which use precise phase information as a basis.

The invention discloses a garbage incineration fly ash filter cake modification method including: first, adding fly ash, sodium carbonate, coal ash and water into a first-stage water washing stirring tank for water washing for three times, using a vacuum filter for solid-liquid separation of filtrate and filter cake after each time of water washing; wherein filtrate separated by first time solid-liquid separation is sent into a sewage tank for subsequent wastewater treatment; the second time and third time solid-liquid separated filtrates are respectively used as the first time and second time water washing water; the third time water washing is clear water washing. The third time solid-liquid separated filter cake is a modified fly ash filter cake, due to the less looseness and smaller viscosity, the feed conveying is smooth, drying machine material attachment is reduced, the strength of material blocks formed during drying of the filter cake is small, wall scrapping is easy, and scattering is smooth, the fly ash filter cake drying process can be performed normally, the problems existed in the real engineering can be solved, and the cement kiln co processing garbage incineration fly ash technology can be improved.

The present invention discloses a method for determining the equivalent static load of the blasting action of the RC beam with lifting wave reinforcement. The method comprises the following steps: (10) acquisition of the static bearing capacity parameters of the component: acquiring static bearing capacity parameters of the component through the quasi-static uniform loading test of the RC beam with lifting wave reinforcement and the quasi-static uniform loading test of the RC beam with the with lifting wave reinforcement of the two-end lifting wave; (20) estimation of the resistance dynamic coefficient: according to the static bearing capacity parameters of the component, estimating the dynamic resistance coefficient of the RC beam; and (30) equivalent static load calculation: according tothe resistance dynamic coefficient, calculating to obtain the equivalent static load of the blasting action of the RC beam with lifting wave reinforcement. According to the method for determining theequivalent static load of the blasting action of the RC beam with lifting wave reinforcement disclosed by the present invention, the error between the calculation result and the actual situation is small.

The invention discloses a solar heat storage-ground source heat pump integrated system based on rainwater storage / infiltration, and belongs to the technical field of energy-saving systems. The system comprises the following five pipeline systems: a solar heat collection system, a vertical and horizontal ground buried pipe heat exchange system, a ground source heat pump system, a rainwater storage / infiltration system and an air conditioning terminal system. The invention is an improvement on the conventional solar-ground source heat pump systems. The system can solve the problem of ground source heat pump heat supply / heat elimination imbalance in the heat supply load dominant areas and the problem of unbalanced underground soil temperature field due to long-term operation; and can effectively eliminate the danger of overheat due to the empty sun exposure of solar heat collectors in summer, prolong the service life of solar heat collectors and increase the comprehensive utilization rate of solar energy. Besides, the rainwater storage / infiltration technique is adopted to effectively improve the heat exchange property of the soil, increase the work efficiency of the solar seasonal heat storage-ground source heat pump system, promote the sustainable recycling of rainwater and effectively reduce the flood disaster and runoff pollution.

The invention relates to an optical field dynamic modulation and spatial multiplexing method based on a reconfigurable hybrid metasurface, and belongs to the technical field of micro-nano optics and light beam shaping application. The hybrid reconfigurable metasurface for realizing optical field dynamic modulation and spatial multiplexing is composed of a composite circular ring array with different geometric sizes and different symmetry axis arrangements. By changing the geometric size of the composite circular ring and the direction of the symmetry axis, the mixed reconfigurable metasurfacecan adjust and control the amplitude and the phase of emergent light beams at will. And optical field complex amplitude distribution in different modes is obtained through two-dimensional full-wave vector calculation. And according to the obtained optical field complex amplitude distribution in different modes, the geometric dimension and the azimuth angle of the composite circular ring are determined through coding, so that the corresponding hybrid reconfigurable metasurface structure array is generated. Dynamic regulation and control and spatial multiplexing of incident light beams by the same hybrid reconfigurable metasurface are achieved by adjusting the state of the phase-change material.

The invention discloses a small body gravitational field modeling method based on gaussian process regression GPR, and belongs to the technical field of deep space exploration. The implementation method comprises the following steps: using the spherical coordinates of a field point near a small body, and obtaining a training set of gravitational field data through a polyhedron method; and using the obtained training set to establish a gaussian process regression GPR model. Then, a gravitational field at the position of a checking point is predicted to obtain a mapping relationship between thefield point and gravitation acceleration, namely modeling calculation is carried out on the gravitational field near the small body quickly and accurately by using the gaussian process regression GPRmethod, and the calculated amount can be reduced, so that the modeling speed is improved, and the requirement of online calculation is met. The method can be applied to deep space exploration, technical support and reference are provided for the establishment of a dynamics environment around the small body in a small body exploration task, and associated engineering problems are solved.

A repairable GO algorithm based on a dynamic Bayesian network comprises the steps of: I, modeling a system into a dynamic repairable GO method model diagram comprising a repairable operator, II, mapping a dynamic repairable part as a dynamic Bayesian network node, and determining a conditional probability table of the dynamic Bayesian network node, and III, determining a set membership of the dynamic Bayesian network node, making calculation through the mature Bayesian network, and finally obtaining a relevant result of reliability modeling, and, if the repairable GO method comprises a static operator, further comprises the steps of: IV, mapping an unrepairable part as a Bayesian network node and determining a conditional probability table of the Bayesian network node, V, determining a node after conversion and a set membership of a Bayesian network node corresponding to an input signal of the node, VI, combining a dynamic Bayesian node and a static node into the complete Bayesian network, and VII, making calculation through the mature Bayesian network to obtain a relevant result of the reliability modeling.

The invention discloses a component-based CMDB propellant mechanical prediction method, relates to a mechanical property prediction method at a wide strain rate, is applicable to the field of CMDB propellant formula mechanical optimization design, and belongs to the field of solid propellant rate dependence mechanical properties. The implementation method comprises the following steps that according to atomic group contribution and selection principle, input parameters obtaining components are selected, a potential-energy function of an adhesive matrix is built, and by quantizing storage modulus and Young modulus, the glass-transition temperature and the Young modulus of the adhesive matrix of a CMDB propellant are calculated. Considering the solid particle strengthening effect, the Youngmodulus of the CMDB propellant is calculated; a rate dependence constitutive model is built through integration; the rate dependence constitutive model can be applied to application fields related tothe CMDB propellant, prediction of the relation between the CMDB propellant molecular structure and the mechanical property is achieved, and engineering problems in the application fields related to the CMDB propellant are solved.

The invention relates to a culturing method for a dominant nitrosation bacterial community. The culturing method comprises the following three culturing stages: stage 1, enriching a mixed bacterial community of nitrosomas and nitromonas, wherein a microbial growth promoter A is used in the process of enrichment; stage 2, carrying out nitromonas elutriation by using a microbial growth promoter D and a high-temperature culture and normal-temperature culture alternate method so as to gradually improve the dominance of nitrosomas and beginning third-stage culture when a nitrosation rate is greater than 50%; and stage 3, reducing the content of dissolved oxygen or increasing a pH value, carrying out further nitromonas elutriation and stability domestication of nitrosomas by using the microbial growth promoter D and terminating culture when the nitrosation rate is stabilized and is 65% or more so as to obtain the dominant nitrosation bacterial community. The culturing method provided by the invention overcomes the problems of instability of partial nitrification in practical application, can shorten the starting time of nitrifying process, rapidly changes the process of a nitrifying reaction, broadens the application scope of partial nitrification and provides guarantee for actual application of a partial nitrification process to real projects.

The invention belongs to the technical field of environmental protection and particularly relates to an optimized design method of a photobioreactor for cultivating microalgae in waste water. The method includes the first step of establishing a chlorella polyculture growth model on the basis of studies of the autotrophic growth kinetics and the heterotrophic growth kinetics of chlorella and obtaining an organism degradation kinetic model on the basis of the chlorella polyculture growth model, the second step of establishing a gas-liquid two-phase two-dimensional transient CFD model where a flow field of the photobioreactor and chlorella biochemical reaction are coupled on the basis of an Euler-Euler two-fluid system, and carrying out a simulation study on dynamic behavior characteristics of the chlorella in the intermittent process where the chlorella degrades organic substances in the gas-liquid two-phase airlift flat-plate photobioreactor, and the third step of finally carrying out experimental verification on a model simulation result according to an experimental curve of the chlorella concentration and the organic substance concentration changing over time. Consequently, the model which is capable of predicting the growth situation of the chlorella and the degradation situation of the organic substances in the photobioreactor is established, and an important theoretical basis is established for optimization design of structural parameters and operating parameters of the photobioreactor.

The invention discloses an optimization method for pressure swing adsorption carbon capture based on Fluent software. The method comprises establishing of an adsorption bed model for adsorbing CO2 andestablishing of a mold for calculating fluid mechanics; and the method comprises the following specific steps: firstly, setting basic parameters of an adsorption bed, and performing model assumptions; then performing numerical simulation on a CO2 adsorption process by utilizing the Fluent software, and establishing a mass, momentum and energy conservation equation; writing user-defined functionsfor solving, and using three user-defined scalars and six user-defined memories; setting initial and boundary conditions of pressure swing adsorption, and simulating the whole adsorption process through a discrete control equation to obtain adsorption results; and when an adsorption process is finished, adjusting the initial or boundary conditions according to the adsorption results to find the optimal adsorption conditions corresponding to the adsorption bed. The method provided by the invention obtains more accurate and more practical fluid flow distribution, component concentration distribution, various temperatures and the like in an adsorption container and optimizes the energy efficiency analysis and adsorption system in the CO2 adsorption process.

The present invention discloses a method for measuring and locating the tops of the virtual tetrahedron of the special-shaped component. In a special-shaped node three-dimensional body, four points which are not in a same surface are chosen to form a virtual tetrahedron. The three-dimensional coordinates of the four points are calculated and the corresponding marks of the four points are marked on the real object of the node. A random point is chosen as a main control point of the node and other points are taken as auxiliary control points. When the node is hanged to the station, firstly the three-dimensional coordinate of the main control point is monitored with an electronic total station at the position of the measuring point, and on the moulding bed of the node, the adjustment is executed by means of equipment to accurately control the plan position and scale height of the main control point. The planar and vertical three-dimensional rotation adjustments are executed while the node takes the main control point as a center until when the monitored reading number of the coordinate of other three auxiliary control points is fit with the calculated value. When the node is measured and is accurately mounted, the node is welded on the positioning device of the moulding bed for temporary fixing. The method of the invention has the advantages of simple principle, reliable method, convenient realization, high work efficiency and broad application sphere.

The invention discloses a phosphogypsum stabilized collapsible loess roadbed material and a preparation method thereof. According to the method disclosed by the invention, phosphogypsum is added intoa mixture composed of fly ash, slaked lime and collapsible loess, through addition of the phosphogypsum, main component calcium sulfate contained in the phosphogypsum can activate activity of the inert material fly ash and accelerate a pozzolanic reaction between lime and the fly ash, and needle-shaped ettringite is generated, so that the method has the effect of further enhancing strength of limeand fly ash stabilized collapsible loess, and the loess has higher strength and rigidity and excellent road performance; Ga<2+> contained in the slaked lime and active SiO2 and Al2O3 contained in thefly ash and the collapsible loess act to form water-containing calcium silicate and calcium aluminate, and the water-containing calcium silicate and calcium aluminate are a basis of formation of thelime and fly ash stabilized collapsible loess; and the roadbed material disclosed by the invention has a reasonable formula and the simple preparation method, and the finished product has better strength, rigidity and good road performance, and is suitable for construction of highways in collapsible loess areas.

The invention discloses a power system transient stability analysis method taking wind power and direct current comprehensive effects into consideration; a system transient steady-state analysis modelwhich is connected with wind power in an alternating-current and direct-current non-parallel transmission mode is established, and the quantitative indexes of large-scale wind power access to systemtransient stability influence are provided; a quantitative analysis method by enabling the wind power and direct current comprehensive effects to be equivalent to system equivalent mechanical power increment is proposed; and a qualitative analysis method considering influence of the wind power and direct current comprehensive effects to change of an acceleration area and a deceleration area is proposed based on equal area determination. According to the method, the implementation is convenient, the analysis method is clearer and more effective, the applicability is high, and the analysis is simple and convenient; and meanwhile the application range is wide, the analysis effect is good, the application scenes are wide, and the problem of practical engineering can be solved.

The invention relates to a simulation calculation method for a combined gap impulse discharge development process. The method comprises the following steps: step 1, establishing an electric field calculation physical model considering charged particle motion in the combined gap impulse discharge development process in finite element software; step 2, determining the potential of a potential suspension conductor in each discharge development stage by combining an electric field calculation result and a charged particle motion simulation result in a pre-discharge stage; and step 3, realizing simulation of a combined gap breakdown development process by taking a condition that the streamer with a relatively low development speed reaches the surface of the potential suspension conductor as a breakdown criterion. According to the method, the actual physical process of the combined gap discharge process can be analyzed, and the discharge mechanism of the combined gap discharge process can bedetermined.