88results about How to "Solve the measurement accuracy" patented technology

The invention provides a track dynamic measuring system and method. The track dynamic measuring system comprises a longitudinal beam, a transverse beam, a total station instrument, a controller, an inertial navigation device, track gauge sensors and a mileage sensor. By using the track dynamic measuring system and method, the track measuring efficiency can be greatly enhanced on the premise of guaranteeing the absolute measuring accuracy of the track, can avoid problems that GNSS signals are missing in long and bid tunnels and the measuring accuracy does not satisfy the use requirement and can realize the balance between the track dynamic measuring accuracy and the track dynamic measuring efficiency.

The invention discloses a compact transient microwave frequency photon measurement system, which comprises a receiving antenna, a microwave power amplifier, a high-speed directly modulated laser, a circulator, a tunable phase-shifting grating, a tunable M-Z interferometer, a first high-speed photon detector, a second high-speed photon detector and a comparator. A microwave signal is loaded to the directly modulated laser of which the wavelength is tunable. By tuning the DC bias voltage of the laser, a positive / negative first-order sideband carrying the microwave frequency information is only generated on two sides of the carrier frequency, and the carrier power is suppressed by using the tunable phase-shifting grating. The filtering is carried out by a tunable M-Z filter, and the carrier wavelength is aligned with a peak value and a valley value at two output ports of the filter by tuning the arm length of the filter. Because the variation tendency of the power at the two output ports along the microwave frequency is reverse, a comparison function is monotonously varied along the microwave frequency in a certain range and further the measurement of the transient microwave frequency can be realized.

A sensor resistance measurer consists of a power module, a keyboard module, a display module, a testing voltage source, a to-be-measured sensor, an operational amplifier, a feedback network, a polarity processing module, an A / D (analog / digital) converter and a numerical value processor. At least two feedback units are connected in parallel to form the feedback network. A sensor resistance measuring method is realized by the aid of measurement initialization, A / D conversion, polarity processing, automatic gear control, automatic zero point calibration and sensor resistance calculating software. A method for obtaining high precise resistance values includes that an attenuation type feedback network of a conventional precise-resistance-value resistor is adopted in a measuring amplifier, so that precise equivalent feedback resistance with the quite high value is obtained. The sensor resistance measurer and the method have the advantages that a high-resistance-value nano sensor with the resistance value higher than 1 G ohm can be precisely measured, large-range dynamic high-precision measurement is realized, voltage added on a resistor of the sensor can be confirmed and can be set in an optional range, a user does not need to adjust the voltage, any special production process requirements are omitted, the sensor resistance measurer is suitable for batch production, and the like.

The invention belongs to the technical field of measurement tools, and in particular relates to a contact measuring head for measuring the thickness of a surface mount technology (SMT) screen plate. The probe comprises a shell, an air guide rail, a probe, a connecting piece, a high-resolution laser ruler, a displacement sensor, a gas pipe joint and a data cable; the measuring head adopts a contact measurement principle, namely a probe ball at the end of the probe which is perpendicular to the SMT screen plate is in contact with the surface of the SMT screen plate, and the probe has a unique vertical movement freedom degree, namely the probe can only move vertically; the own weight of the probe is counteracted by a precise spring in the probe; the other end of the probe is connected with the high-resolution laser ruler which is arranged in parallel to the vertical direction of the probe; and the displacement change of the probe in the vertical direction can be detected in real time by a small laser displacement sensor in the probe.

The invention relates to a device and a method for measuring crack expanding rate of a compact tension specimen, which are applied to continuous high-accuracy measuring of fatigue crack expanding, stress corrosion cracking, corrosion fatigue and other experiments of the compact tension specimen. The device comprises the following hardware of a computer, a GPIB (general purpose interface bus ) card, a multi-channel high-power relay card, a high-accuracy nanovolt micro-ohmmeter, a data switching unit, a high-stability direct current power supply, a shielding conducting wire or a double-strand insulation platinum wire. The device comprises the following software of direct current potential drop crack expanding rate measuring software and a user interface thereof. The device has the advantage that the relay switch is controlled by the direct current potential drop crack expanding rate measuring software to reversely change the direction of the direct current, so as to solve the problem of interference to the measuring accuracy and stability by the contact resistances of lead wire and specimen and electric potential produced by the temperature difference at both ends of the lead wire.

The invention discloses a method for locking laser wavelength for gas detection. The method comprises the steps of sending out laser scanning signals in a step-by-step way at regular time, pushing in a gas reference cell in a detection light path; selecting at least one point location in a space scanning range, changing a little current every time when a space is scanned, continuously collecting for at least one scanning cycle, and producing an absorption spectrum according to the obtained optical signals; adjusting the laser wavelength according to gas absorption positions in the absorption spectrum. The invention also provides a device for locking the laser wavelength for gas detection. Compared with an original method and an original device, according to the method and the device provided by the invention, a set of laser beam splitter and a set of reference light detection circuit are reduced, the laser output light intensity can be completely used for detecting, long-range detection is carried out favorably, and the cost can be also reduced because of the reduction of the reference light detection circuit.

The invention relates to the technical field of measuring equipment and particularly relates to a measuring instrument for a small modulus gear M value. The measuring instrument comprises an assembling shaft system, a measuring mechanism, a rail mechanism and a base, wherein the measuring mechanism is arranged on the rail mechanism; the rail mechanism is arranged on the base; the assembling shaft system is arranged on the base; the assembling shaft system is driven to rotate by a motor; a to-be-measured gear is arranged at the upper end of the assembling shaft system; and the measuring mechanism comprises an X directional parallel leaf spring mechanism and a Y directional parallel leaf spring mechanism. According to the invention, a common alternating current servo motor can be adopted for achieving an indexing function; the measuring speed is high; no precise circular grating is required; the cost is lowered; use and maintenance are convenient; the measuring instrument is suitable for the working condition of domestic gear batch production at present, can meet the requirement of quick gear comprehensive check, can comprehensively control the gear quality, can be used for measuring the gears of other modulus and can effectively increase the production efficiency.

The invention relates to the technical field of laser measurement, in particular to a laser ranging optical axis consistency dynamic calibration method and system. The laser ranging system comprises alaser 1, an emission light path, a receiving light path and a signal receiving and processing device 2, the light path is provided with a laser receiving and transmitting lens 3, a first fixed reflecting mirror 4, a hollow reflecting mirror 5, an FSM reflecting mirror 6, a piezoelectric deflection table 7, a narrow-band light filter 8 and a receiving optical assembly 9. The transmitting light path is adjusted for preset manner scanning, and the emission angle corresponding to the echo power peak value point meeting the system receiving-emitting optical axis error range requirement can be obtained through analysis and comparison, the piezoelectric deflection table is used for driving the FSM reflecting mirror to deflect, the emission light path is controlled to emit laser along the angle corresponding to the power peak value point, and therefore the consistency of the laser receiving-emitting optical axis is guaranteed, and the problem that the measurement range and precision of the ranging system are sharply reduced due to the fact that the parallelism of the laser receiving-emitting optical axis is degraded is solved.

The invention discloses an error counter for an electric energy meter. The error counter comprises a single chip, a 10M constant-temperature crystal oscillator, a 5-frequency divider and a 100-frequency divider, wherein four counters are carried by the single chip, and two of the counters are provided with a capturing function. For the error counter provided by the invention, the capturing interrupting and pulse modulation means are adopted, the fuzzy control principle is adopted, and an error counting method with setting parameters subjected to optimized treatment is further adopted, so that the precision for collecting pulses is guaranteed from aspects of hardware design and software design. In addition, the error counter provided by the invention is especially used for solving the problem of controlling the measuring precision and measuring time of low-frequency pulse by the low-frequency pulse. Under the condition of ensuring the measuring precision, the working efficiency is greatly improved.

The invention discloses a supervision control method of super high-rise building engineering survey. The supervision control method is characterized by comprising the following steps: a, carrying outhorizontal control survey; b, carrying out vertical control survey; c, carrying out laser scanning analog three-dimensional measurement on buildings by using a three-dimensional laser scanner; d, enabling a coordinate system of a construction horizontal control network and a construction vertical control system to be consistent with coordinates of a design construction drawing and a height system;carrying out deformation supervision inspection on to-be-tested buildings by adopting standards corresponding to geographical location; e, carrying out layout survey, and laying out according to thecoordinates; when the layout is different from drawing size, requiring designers, supervision personnel and construction personnel to carry out on-site check treatment; needing to protect measurementcontrol points and frequently checking to prevent errors. The supervision control method disclosed by the invention can be used for systematic supervision of high-rise buildings, has high supervisionaccuracy and is simple; the problems of survey accuracy, verticality and planar location of super high-rise buildings are solved.

The invention discloses a self-adaptation compound feedback optical current transformer and a method for determining current and belongs to the field of electric system high-voltage circuit current measuring and controlling applications. The self-adaptation compound feedback optical current transformer comprises a magneto-optic sensing unit which is a double-ring compound magneto-optic sensing unit and N single-stage magneto-optic sensing units. The current transformer is formed by arranging an intelligent following-adjusting light source, optical splitters, front-mounted optical detectors, rear-mounted optical detectors, the magneto-optic sensing unit, collimators, polarizers and polarization analyzers according to an optical transmission optical path. Meanwhile, the invention provides a method for determining current. The compound sensing technology is adopted, and therefore the problem that because of time-varying parameters, the measurement precision of the optical current transformer is low is solved; the optical sensing loop close-loop negative feedback structure is adopted for eliminating random variations, caused by environment temperature, of light intensity on the background of the optical current transformer, and the measurement precision is further improved.

The invention relates to a device for measuring a return flow of L-shaped communicating pipe drilling liquid and a method for measuring a return flow of L-shaped communicating pipe drilling liquid. The device for measuring a return flow of L-shaped communicating pipe drilling liquid consists of an optical liquid level sensor, an L-shaped communicating pipe, a flare pipe, a communication pipe bracket, a signal conditioning and pre-processing device, a data acquiring unit, a client computer and a sound and light alarm device, wherein the pipeline of the flare pipe is provided with an L-shaped communicating pipe; the L-shaped communicating pipe and the flare pipe form a communicating vessel; the vertical position of the window of the L-shaped communicating pipe is positioned between a pipeline flange plate of the flare pipe and the lower edge of a return pipeline; the circumferential direction of the window of the L-shaped communicating pipe anticlockwise rotate between the extended lines of the return pipeline central line from the intersecting line of the return pipeline and the pipeline of the flare pipe; and the optical liquid level sensor is arranged on the L-shaped communicating pipe bracket. In the invention, the pre-warning time is early; the detection precision is high; workers at the drilling site have more sufficient time to close the well; and blowout accidents are effectively prevented.

The invention discloses a topographic special point positioning method for a three-antenna interference delay Doppler radar altimeter, and mainly solves a problem that a conventional method is lower in height measurement precision and ground resolution. The method comprises the steps: establishing an echo signal model of the three-antenna interference delay Doppler radar altimeter; calculating a noise power estimation and detection threshold of an echo signal; delineating an interference window, and obtaining all ground units whose amplitude values are greater than the detection threshold; selecting a special point, and selecting a ground unit without aliasing; extracting an interference phase, and obtaining an inclined angle of the ground unit relative to the normal of an antenna array; and estimating the three-dimensional coordinates of the special point according to a distance corresponding to the special point in the interference window, the inclined angle of the ground unit relative to the normal of the antenna array and an inclined angle between the center of a Doppler channel where the special point is located and the heading direction. The method improves the height measurement precision of the radar altimeter and the resolution in a direction perpendicular to the heading direction, can obtain more special points and gives the three-dimensional coordinate information, and can be used for locating a target during topographical matching.

The invention provides a fluxgate digital current sensor based on a pulse amplitude detection method. The fluxgate digital current sensor comprises a probe unit, an excitation unit, a signal processing unit, an MCU main control unit and an output unit, wherein the excitation unit is connected with the probe unit, the excitation unit generates a sine wave signal, sine excitation current with the angular frequency of omega is applied to an excitation coil of the probe unit, and an excitation magnetic field He is generated; the probe unit is connected through the signal processing unit and is used for converting Ip measurement to be measured into excitation current Iex; the signal processing unit is connected with the main control unit and converts the excitation current Iex into voltage measurement Uex through a sampling resistor Rs and an operational amplifier; the main control unit MCU mainly completes the frequency control, detection and data processing functions of the excitation unit, and calculates the current Ip to be measured according to the sampled voltage Uex; the output unit is a CAN bus interface, is connected with the main control unit, and provides a communication interface for a sensor and other main control equipment.

The invention discloses an error prediction and real-time compensation technology for a five-degree-of-freedom hybrid robot based on a neural network. The technology comprises the following steps of (1) pose error decomposition on the hybrid robot, (2) pose error measurement and prediction of a parallel mechanism, (3) series swivel error prediction, (4) joint error compensation of the hybrid robot, (5) compensation neural network training and (6) constructing of a joint error compensator. According to the technology, prediction and compensation are implemented by directly utilizing error measurement data of the robot, the robot tail end pose errors caused by robot geometric errors and non-geometric factors such as gaps, friction, temperature and gravity can be compensated at the same time, the technology belongs to a comprehensive error compensation method, and the compensation effect is obviously superior to that of a traditional error compensation method based on geometric error identification.

The invention discloses a formation layout and installation system for a three-axis stabilization satellite. In order to meet the formation requirement for the satellite, formation thrusters need to be added to the satellite on the basis of a posture control thruster and a track control thruster; under a launching state, effective load and solar battery arrays of the satellite are drawn to the periphery of the satellite; when the satellite stays on the track, the effective load and the solar battery arrays are all spread in the Xa direction of the flight direction of the satellite to ensure that plumes of the formation thrusters do not intervene in the solar battery arrays and the effective load, and guarantee the maximization of the efficiency of the formation thrusters; according to theflight posture of the satellite, the formation thrusters are divided into two groups, the two groups are distributed at a +- Ya side of the satellite separately, the planes of the thrusters are perpendicular to the direction, pointing to the ground, of the satellite, and the formation thrusters cooperate with one another to pass through an average centroid of the satellite when the satellite staysat an on-track flight state. By adopting the formation layout and installation system, the satellite installation accuracy of the formation thrusters and the manufacturability of operation implementation are ensured; the demands of the formation thrusters for installation, accuracy measurement and formation control in the satellite can be effectively met.

The invention aims to provide a circuit and a method for measuring resistance of a variable resistor. The circuit comprises single-chip microcomputers, a capacitor, a to-be-tested variable resistor Rx and a standard resistor R1. One end of the capacitor C is connected with the single-chip microcomputer GP0, and the other end of the capacitor C is connected with the ground. One end of the standard resistor R1 is connected with one end of the capacitor C, and the other end of the standard resistor R1 is connected with the single-chip microcomputer GP1. One end of the to-be-tested variable resistor Rx is connected with the single-chip microcomputer GP2, and the other end of the to-be-tested variable resistor Rx is connected with the other end of the standard resistor R1. The other end of the to-be-tested variable resistor Rx is connected with the other end of the standard resistor R1. According to the invention, a charging time T1 of a charge and discharge loop of the standard resistor R1 and the capacitor C and a charging time T2 of a charge and discharge loop between the serially-connected to-be-tested variable resistor Rx and the standard resistor R1 and the capacitor C are measured, and the resistance of the to-be-tested variable resistor Rx is calculated through a mode of Rx=R1*(T2-T1) / T1. The method provided by the invention solves the contradiction between measurement precision and measurement time in the circuit for measuring the resistance of a variable resistor by measuring the charge and discharge time of a capacitor in the prior art, and can obtain a good measurement result for a small variable resistor.

The invention discloses an automatic force adjustment device for a micro-Vickers hardness meter. The automatic force adjustment device comprises a force adjustment unit and a handle. The handle is fixed to the force adjustment unit. The automatic force adjustment device is characterized in that the automatic force adjustment device comprises a variable load control board, a permanent-magnet synchronous motor, a variable load motor connection shaft and a variable load optical disk; the variable load control board controls the permanent-magnet synchronous motor to work by signals; the permanent-magnet synchronous motor is connected to the variable load optical disk by the variable load motor connection shaft; and a rotation speed of the permanent-magnet synchronous motor is in a range of 6-10 r / min. The automatic force adjustment device for a micro-Vickers hardness meter prevents that in manual rotation, over-fast falling of a weight is caused by weight gravity so that the weight impacts on a weight bar, and thoroughly solves the problem that the impact produced by loading force conversion influences measurement accuracy and a service life of an instrument.

The invention discloses a method for measuring a wire rope of a laying winch. The method comprises the following steps: discharging or retracting the wire rope by the winch, changing direction of the wire rope after the wire rope passes through a pulley of a measuring device, driving the pulley to rotate by the wire rope, and acquiring an output voltage signal of a tachogenerator through corresponding arrangement of a gear ring and the tachogenerator; enabling a linear transducer to generate periodic pulse current through corresponding arrangement of a spoke and the linear transducer; acquiring a tension output signal through a tension sensor on a mandrel; and calculating the speed, length and tension values for discharging and retracting the wire rope through the laying winch control device, and controlling the laying winch in real time to correct the discharging and retracting of the wire rope in time. The invention also discloses the measuring device used by the method, which guides the wire rope discharged by the laying winch according to a set direction so as to improve the measuring accuracy and response time of parameters of laying wire ropes; and the winch is not positioned on the central line of a laying operating line so as to effectively utilize space.

The invention belongs to the field of power equipment control technology, and relates to a measuring system and a measuring method for measuring the actuation time of a high-voltage breaker of a non-load transformer loop. The system comprises a high-voltage-side transformer, a low-voltage-side transformer and a single-chip microcomputer module. The control instruction output end of the single-chip microcomputer module is connected with a breaker drive circuit. The signal input end of the single-chip microcomputer module is connected with a disconnection detection circuit and a connection detection circuit. The disconnection detection circuit is connected with the high-voltage-side transformer via a high-voltage signal acquisition terminal. The connection detection circuit is connected with the high-voltage-side transformer and the low-voltage-side transformer respectively via the high-voltage signal acquisition terminal and a low-voltage signal acquisition terminal. According to the technical scheme of the invention, the connection time duration and the disconnection time duration of the high-voltage breaker in the non-load transformer loop in the high-voltage state can be accurately measured.

The present invention provides a handheld laser scanner for indoor door and window measurement. The scanner comprises a gyroscope module (11), a scanning module (12), an indication laser unit (13), acontrol unit (14), a wireless transmitting-receiving module (15) and a battery pack (16). The scanner is employed to perform measurement of dimensions of doors and windows indoors to obtain accurate measurement data, a mobile phone client is employed to achieve record and management of the measurement data, a corresponding design is cooperated, and therefore, compared to a traditional measurementmeans, the scanner provided by the invention can perform measurement of doors and windows indoors with no need for professionals, common usage personnel only need simple operation to obtain a measurement result being the same a measurement result obtained by the professionals, the scanner is employed to greatly reduce the measurement time compared to the traditional measurement mode, measurement of common doors and windows only needs tens of seconds, automatic record can be performed, and the working efficiency can be greatly improved.

The invention discloses a zero-flux hall large-current sensor structure, which comprises an upper half part structure, a lower half part structure and a connecting part structure, wherein the connecting part structure comprises an upper installation plate and a lower installation plate, which are identical to each other, the upper half part structure comprises two superimposed aluminum plates, two ends of the aluminum plate on the upper part are respectively provided with a circular hole, the periphery of the aluminum plate on the lower part is provided with a plurality of tapping holes C corresponding to tapping holes A on an upper installation plate, the aluminum plate on the lower part and the two upper installation plates are fixed by adopting a screw to penetrate the tapping holes A and the tapping holes C, the lower half part structure comprises a U-shaped aluminum plate, the peripheries of two top ends of the U-shaped aluminum plate are respectively provided with tapping holes D, two top ends of the U-shaped aluminum plates and two lower installation plates are fixed by adopting a screw to penetrate tapping holes B and the tapping holes D, and the upper installation plates and lower installation plates are tightened through a bolt running through a hole on a suspension loop. Through the structural mode, by adjusting an intermediate connecting mechanism, the position of a magnetic core is very easy to adjust.

A three-point positioning rotary platform used for rail wheel measurement support; the three-point positioning rotary platform includes three sets of support structures; these three sets of support structures are evenly arranged on the circumference of the same plane; each set of support structures includes a a triangular centering slide table, a rotary support shaft arranged on the top of the triangular centering slide table, an end face bearing provided at the front end of the rotary support shaft, a rotary servo motor provided at the rear end of the rotary support shaft, and The slide base located at the bottom of the triangular centering slide, the slide screw located on the slide base, and the slide servo motor driving the slide screw; the rotating support in the three sets of supporting structures The ends of the axles combine to form a support platform for supporting the rail wheels. The invention realizes the technical effects of reasonable design, low cost, and high measurement efficiency and accuracy.

The invention provides a mechanical decontamination type water level alarm device and a use method thereof, and belongs to the field of alarm devices. The mechanical decontamination type water level alarm device comprises two supporting frames, an alarm lamp is installed at the top end of one side of one supporting frame, and water level detection probes used for detecting the river water level are installed at the bottom and in the middle of one side of the other supporting frame; a flood prevention mechanism is arranged between the two supporting frames. By arranging a limiting mechanism, a bowl-shaped paddle can rotate under the action of water flow or flowing wind, then a brush is driven to rotate to be matched with an annular spring to drive the brush to move up and down, and the brush can clean the ends of the water level detection probes in the moving process; most scales on the end parts of the water level detection probes can be cleaned, the scales on the water level detection probes are prevented from influencing the detection precision of the water level detection probes, and the problem that the measurement precision of the sensor is influenced by the scale easily generated on the surface of the sensor when the sensor at a low water level is soaked in river water for a long time in long-term use is solved.

The invention discloses an array resistivity focusing system and method in a laboratory. The system involves a voltage-controlled current source, a focusing controller, a main transmitting electrode A<0>, shielding electrodes A<1>-A<n-1>, shielding electrodes A<1>'-A<n-1>' which are symmetrical to the shielding electrodes A<1>-A<n-1>, backflow electrodes A<n> and A<n>', two pairs of supervision electrodes M<1>, M<2> and M<1>', M<2>' arranged between A<0> and A<1> and between A<0> and A<1>'. According to the array resistivity focusing system and focusing method in the laboratory, a digital focusing synthesis method is adopted between the main transmitting electrode and the shielding electrodes, hardware focusing cascading is adopted between the shielding electrodes and the shielding electrodes, and the digital focusing and the hardware focusing are combined, so that the problem of inaccurate measurement precision caused by residual potential of pure hardware focusing is well solved. Meanwhile, the problem of small-signal measurement precision of a pure digital circuit is solved, and the complexity of pure digital focusing calculation is greatly simplified. The focusing controller can carry out corresponding addition or deletion according to the increase or decrease of the array electrodes so as to meet the requirements of the laboratory on detection depth and resolution, and isflexible and changeable; and the V-I design of the backflow electrodes can realize deeper-stratum detection according to experiment requirements.

The invention relates to a flow measuring device, in particular to a low-pressure-drop super acceleration gauge. The low-pressure-drop super acceleration gauge comprises a Venturi tube, and is characterized in that the Venturi tube is an inserted type external Venturi tube, a rectangular tubular generator is matched in the Venturi tube, and two pressure tapping tubes perpendicular to the axis direction of the Venturi tube and the rectangular tubular generator are matched with the Venturi tube and the rectangular tubular generator. The low-pressure-drop super acceleration gauge is unique in structure, solves the problems that accuracy is low and measuring range is narrow during low-Reynolds-number fluid measurement, solves the problems that under low pressure drop, measurement accuracy is low and measuring range is narrow, and achieves the purpose of installing and replacing a measuring instrument online.

The invention relates to a multilevel wind power current transformation device without an AC / DC current sensor, and belongs to the technical field of power generation, power transformation or power distribution. The current transformation device is connected in series between a wind power generator set and a power grid. The current transformation device comprises a network side controller, an MPPT controller, a first current transformation unit, a second current transformation unit and a trap filter. The first current transformation unit, the second current transformation unit and the trap filter are connected in series in turn, and each unit in the current transformation device is controlled to realize feedforward control through each controller so as to realize grid connection power generation of the wind power generator set. According to the current transformation device, the harmonic component possibly brought into the power grid by the wind power generator set in grid connection can be reduced so that possible harm of the harmonic component to the power grid can be indirectly eliminated.

The invention discloses a three-dimensional chemical industry park establishing method. According to the three-dimensional chemical industry park establishing method, three-dimensional information of a three-dimensional chemical industry park is obtained according to characteristics of a to-be-scanned target object by adopting different types of three-dimensional laser scanners, the contradiction between the scanning precision and the scanning speed is well solved, by utilizing the conversion relationship between the WGS-84 standard coordinate of the target and the coordinates measured by the three-dimensional laser scanners, three-dimensional data obtained by the three-dimensional laser scanners is conveniently converted into the WGS-84 standard coordinate system which is universal to the latest 2,000 coordinate system, so that the obtained data can be directly applied to engineering and management, and the three-dimensional chemical industry park establishing method conforms to the current GIS (geographic information system) technical standard, and has great application value.

The invention discloses a controller performance analysis method based on adaptive sampling, and belongs to the technical field of wireless communication networks. For characteristics of a data streamin an SDN, network overhead factors for measuring controller performances are analyzed, a network overhead mathematical model is built; and existing mainstream SDN controllers (a POX controller, a FloodLight controller, an RYU controller, an ONOS controller and an OpenDayLight controller) are systematically analyzed and compared by means of an adaptive sampling algorithm, and performance indexesof the controllers are quantitatively analyzed, so that a practical and effective research program is provided for future researchers. It shows that the analysis method has the advantages that the SDNcontrollers are systematically and comprehensively analyzed, the relation between the measurement precision and the network overhead is well solved, and therefore SDN controller resources can be fully utilized.

The invention discloses a carrier phase high-precision GNSS receiver group delay measurement method and system; the method comprises the steps: enabling a narrowband spread spectrum signal to pass through a to-be-measured group delay characteristic channel, and obtaining a code phase measurement value and a carrier phase measurement value after the narrowband spread spectrum signal is captured and tracked; then, approximating the group delay into a parabolic function by utilizing the characteristic that the group delay in a narrow-band signal passband changes gently, and traversing parabolic parameters and integer ambiguity; and finally, when the difference value between the group delay characteristic obtained by traversing the parabola parameter and the group delay characteristic obtained by traversing the combination of the integer ambiguity and the measured carrier phase is minimum, determining that the group delay characteristic corresponding to the parabola parameter is the actual group delay characteristic of the channel; meanwhile, the group delay measurement of any frequency resolution can be realized by changing the frequency range of the frequency division multiple access signal.