887results about "Level indicators by pressure measurement" patented technology

The invention discloses a coastal protection dam settlement monitoring method, and belongs to the technical field of hydraulic engineering safety monitoring. The method comprises the steps that a longitudinal monitoring section is arranged on the slope surface of the back sea side of a dam, a three-measuring-line fiber grating sensor array is arranged, and vertical displacement and horizontal dip angle data are periodically collected through a synchronous triggering unit; establishing a vertical displacement-horizontal dip angle joint analysis model by using a multi-source data fusion module, and eliminating tide level interference through a Kalman filtering algorithm to generate a settlement distribution curve; and triggering third-level to first-level early warning signals based on the grading early warning rule, and transmitting the signals to the terminal equipment. The problems that a traditional monitoring method cannot effectively separate tidal interference, the real-time performance is poor, and multi-dimensional data collaborative analysis is insufficient are solved, high-precision settlement monitoring, complex environment anti-interference and rapid emergency response are achieved through multi-measuring-line sensor deployment, dynamic filtering optimization and a graded early warning mechanism, and the method is suitable for large-scale popularization and application. And the reliability and timeliness of dam safety monitoring are obviously improved.

The invention relates to the technical field of industrial automation control, in particular to a container liquid level measurement method, system and equipment of a pressure sensor and a medium, and provides a method for eliminating gas phase pressure influence based on a double-sensor differential measurement mechanism and dynamically correcting liquid density and sensor drift errors in combination with a temperature compensation model. The temperature data are linked in real time through a three-dimensional compensation function, density calculation and drift correction are synchronously adjusted, and multi-parameter dynamic decoupling and self-adaptive compensation are achieved; a collaborative measurement mechanism is adopted to integrate bottom and top sensor data, and a built-in temperature probe and a preset threshold are combined to complete multi-source signal fusion and compensation calculation; a dynamic calibration method is designed, and system errors are eliminated through reference pressure point calibration and structure coefficient correction; constructing a closed-loop signal processing flow, and integrating high-precision analog-to-digital conversion, digital filtering and real-time algorithm to output a compensated liquid level value; the method improves the measurement precision and stability, and is suitable for temperature change, gas phase pressure fluctuation and multi-medium scenes.

The invention discloses a high-precision flow online monitoring device and method for a siltation section, and belongs to the technical field of hydrological monitoring. The device comprises a sensing terminal, an edge terminal and a mounting mechanism, the sensing terminal is integrated with an upper and lower section layered speed measurement module, an underwater distance measurement module, a first absolute pressure type water level measurement module and an attitude and temperature sensor, and vertical section flow velocity data is obtained by receiving water body reflection signals in a time-sharing manner; and the dynamic deposition section area is corrected in real time in combination with ultrasonic ranging. And the edge terminal compensates water level measurement data by using atmospheric pressure, and calculates the flow through fusion of a telemetering module. The installation mechanism supports fixed or telescopic installation, and the height of the installation mechanism is automatically adjusted according to the distance between a deposition layer and equipment. The method comprises the steps of dynamically correcting the section, calculating the flow through layered integration and compensating errors of multiple sensors, the problems of large area deviation, high operation and maintenance cost and the like caused by sedimentation in a traditional flow measurement technology are solved, and high-precision online monitoring under the high-sand-content complex flow state is achieved.

The invention discloses an intelligent water level monitoring system and a data transmission method thereof, and belongs to the technical field of Internet of Things sensing. The system comprises a distributed water level sensing node, an edge computing gateway and a cloud management platform, wherein the sensing node is integrated with a piezoresistive water level transmitter and an adaptive Kalman filtering module; the data transmission method comprises a dynamic threshold triggering mechanism and a compression algorithm based on improved Huffman coding, and low-power-consumption and high-reliability transmission is realized by optimizing transmission frequency and a data packet structure. The edge computing gateway is internally provided with an LSTM water level prediction model, historical data are analyzed through an LSTM neural network, and an early warning signal is generated in real time. And the cloud management platform stores the key data by adopting a block chain technology. Through multi-sensor data fusion and layered encryption transmission, the water level monitoring error rate is reduced to + / -0.5 cm, the data transmission energy consumption is reduced by 40%, and the monitoring efficiency and the data safety are remarkably improved in flood early warning and reservoir management scenes.

Apparatus and methods for monitoring the status of a floating roof. The floating-roof tank assembly has: an impermeable roof section, and a floating-roof seal configured to span between the impermeable roof section and components of a container. One or more deformable floats are attached to the roof section to provide buoyancy so that the roof floats on top of the liquid contained in the container. To monitor the status of the floating roof tank, it is provided with a fiber optic sensor array comprising one or more fiber optic sensors. A light source configured to transmit light to the fiber optic sensors and a receiver configured to detect light from each fiber optic cable after it has interacted with the fiber optic cable. Based on the received light, a controller configured to process the light received by the receiver to determine the status of the floating roof tank.

The invention belongs to the technical field of water conservancy monitoring, and discloses a water conservancy water level monitoring device and method, and the method comprises the steps: a monitoring point arrangement module of a monitoring mechanism reasonably arranges the number and positions of monitoring points; the flow velocity monitoring module monitors the water velocity; the meteorological data acquisition module acquires meteorological data; the echo sounder emits sound waves, and the water depth is calculated according to the sound wave propagation time and the sound velocity in water; the pressure water level gauge, the laser water level gauge and the radar water level gauge monitor the water level of water conservancy. The echo data analysis module analyzes the echo data; the comprehensive analysis module comprehensively analyzes the water level; the predictive analysis module predicts a water level trend and potential risks. The water level of water conservancy is monitored through various water level gauges, cross validation and high precision are achieved, and the sediment deposition thickness is accurately calculated by analyzing echo data; the comprehensive analysis module comprehensively evaluates the water level; the prediction analysis module integrates various monitoring equipment data and meteorological data, and predicts the water level trend and potential risks.

The invention discloses a monitoring system, belongs to the technical field of liquid level monitoring, and particularly relates to a hot well liquid level remote transmission monitoring system which comprises a signal acquisition unit, an automatic control unit and a cloud platform unit, and the signal acquisition unit is composed of a liquid level acquisition module and a visual module; the liquid level acquisition module and the visual module are used for double acquisition of liquid level values and data processing, filtering processing, temperature compensation processing and vibration compensation processing are carried out on two signals respectively, then data correction is carried out, stable and accurate reading data are obtained, meanwhile, the cloud platform unit is used for achieving real-time display of identification results, and the identification accuracy is improved. According to the system, unmanned and real-time monitoring of the boiler double-color liquid level meter is achieved, meanwhile, the recognition result is stable, and the safety of factory production is guaranteed.

The invention discloses a rock hydraulics-based high-position separation water monitoring and drainage control method, which comprises the following steps of: determining a separation water development position according to an early-stage exploration result; a monitoring drill hole and a drainage drill hole which are communicated with the separation water are constructed on the ground surface above the development position of the separation water; a water pressure sensor is arranged at the bottom in the monitoring drill hole; a water suction pump is arranged in the drainage drill hole; a plurality of micro-seismic sensors are arranged in a roof rock stratum of the working face at set intervals, and the development height of the water flowing fractured zone is determined according to micro-seismic signals collected by the micro-seismic sensors; determining the thickness of a separation layer water-resisting layer according to the development height of the water flowing fractured zone; determining an abscission water warning water head according to the thickness of the abscission water water-resisting layer; determining a warning water level according to the separation water warning water head and the separation water bottom plate elevation obtained through early-stage exploration, and setting the determined separation water warning water level as an early warning water level; the water level data in the monitoring drill hole are collected in real time, the real-time water level is obtained, when the real-time water head exceeds the early warning water level, the water suction pump is started to pump separation water, and separation water level control is achieved.

The utility model discloses a water purifier for detecting the liquid level through pressure sensors, and relates to the technical field of liquid level detection of water purifiers, the water purifier comprises a water purifier water tank and a water pipe fixedly arranged on the lower portion, micro pressure sensors are arranged on the two sides of the water pipe, a square head fixedly connected with the water pipe is arranged on the lower portion of the water purifier water tank, and a plurality of transverse shafts A are slidably arranged in the middles of the two sides of the square head; clamping mechanisms are arranged at the two ends of each transverse shaft A, two transverse fixing plates fixedly penetrate through the two ends of each transverse shaft A, sealing plugs A are fixedly arranged in the middles of the surfaces of the opposite sides of the transverse fixing plates, transverse shafts B are fixedly arranged in the middles of the surfaces of the sides of the sealing plugs A, and sealing plugs B are fixedly arranged at one ends of the transverse shafts B. The problems that real-time continuous linear detection cannot be achieved, the detection precision is not high, high-precision liquid level detection cannot be achieved, more functions cannot be provided on the water purifier, and replacement is inconvenient are solved.

The invention provides an underwater robot self-positioning platform based on multi-feature and multi-modal information fusion, and the platform is installed on an underwater robot, and comprises a visual sensing module which is used for collecting image information of an underwater environment, and extracting visual point features and visual line features from the image information; the acoustic measurement module is used for providing three-axis speed information and low-frequency pose information of the underwater robot based on the Doppler principle; the pressure measuring module is used for measuring water depth information of the underwater robot on the basis of a fluid statics principle; and the data processing and optimizing module is used for fusing the visual point features, the visual line features, the three-axis speed information, the low-frequency pose information and the water depth information on the basis of a factor graph optimizing framework so as to realize positioning and mapping. Compared with a traditional system, the self-positioning platform provided by the invention realizes tight coupling joint optimization of point-line features and acoustics and pressure sensor information, can stably operate in extreme underwater environments with low texture, turbidity and the like, and realizes high-precision underwater synchronous positioning and map construction.

Methods, apparatus, and systems for determining a level of a liquid in a liquid-containing vessel are disclosed. The liquid-containing vessel may be fluidically connected to a displacer cage. The method may include obtaining, with a load measurement device, a weight force of a displacer suspended from the load measurement device and disposed within the displacer cage. The method may also include submerging the displacer into the liquid and obtaining, with the load measurement device, a net force acting on the displacer. The method may further include obtaining, with a liquid density measurement sensor disposed within the displacer cage, a liquid density at a first location of the liquid. The method may still further include determining, using, at least, the net force and the liquid density at the first location of the liquid, the level of the liquid in the vessel.

The invention discloses a river water level detection method, and relates to the technical field of computer processing, and the method comprises the following steps: S01, presetting a distributed pressure sensor array in each target collection region to obtain underwater pressure data k and real-time water flow data v of a plurality of target collection regions of a river to be detected; s02, establishing a dynamic pressure water level model based on the water flow direction pressure conduction quantity estimation of the plurality of target acquisition areas in combination with real-time water flow velocity and wave period parameters; s03, performing signal attenuation compensation on the underwater pressure data according to the dynamic pressure water level model to obtain initial water level data; s04, multi-source data fusion calibration is carried out on the preliminary water level data, a river water level detection result is generated, and the result comprises a wave height frequency spectrum and a water level change curve after peak elimination correction; and S05, generating a wave energy spectral density map according to the calibrated water level data, performing real-time comparison according to the wave energy spectral density map and a preset threshold value, and performing result return according to a comparison structure. The small-wave-height short-period wave measurement precision and the water level detection reliability are remarkably improved, the intelligent flood prevention early warning and dynamic adjusting capacity is achieved, and it is guaranteed that data collection is accurate and consistent.

The invention relates to an anti-interference intelligent liquid level transmitter system which comprises a measuring unit used for acquiring an original liquid level signal; the anti-interference processing unit is in signal connection with the measuring unit and is used for executing anti-interference algorithm processing on the original liquid level signal, and the anti-interference algorithm processing includes adopting an acceleration compensation algorithm and a dynamic filtering algorithm to eliminate measuring errors caused by mechanical vibration and medium flow; and the output unit is in signal connection with the anti-interference processing unit and is used for outputting the standardized liquid level signal. The problem that a traditional static filtering algorithm cannot adapt to a dynamically changing vibration environment in real time is solved.

The invention discloses a pipe network safety monitoring method and device, and the method comprises the steps: obtaining a topological structure and historical liquid level data of a target pipe network, and dividing the target pipe network into a plurality of pipe network sub-regions; based on a preset monitoring period, obtaining a radar liquid level value and a pressure liquid level value of the pipe network sub-region, and generating a fusion liquid level value of the pipe network sub-region; in response to the fact that the fusion liquid level value of the pipe network sub-area is larger than a preset liquid level early warning value, it is judged that the pipe network sub-area is a liquid level abnormal area, multiple associated sub-areas of the liquid level abnormal area are determined, and the liquid level trend of the liquid level abnormal area is compared with the liquid level trend of the multiple associated sub-areas; and in response to the fact that the multiple associated sub-regions are consistent with the liquid level trend of the abnormal liquid level region, judging that the abnormal liquid level region is an early warning triggering region, and correspondingly generating a safety alarm. By adopting the method and the device, the multi-source liquid level data and the pipe network topological structure can be combined, the internal interference characteristics of the pipe network are considered, and global analysis is performed, so that the accuracy of liquid level monitoring is improved, and the reliability of safety alarm is improved.

The invention belongs to the technical field of ocean sampling, and provides a pneumatic throwing type multi-channel self-sinking and floating trace seawater sampling device and a pneumatic throwing type multi-channel self-sinking and floating trace seawater sampling method. The device comprises a portable gas cylinder, a casting track, a self-sinking and floating type trace seawater sampler shell, a fixing frame, a pressure sensor, a control bin and the like, and after a seawater sample is collected, a fixing agent can be injected into the seawater sample to fix microorganisms in the seawater sample and the like. And the self-sinking and floating trace seawater sampler is far away from the trace element precipitation influence area of the scientific investigation ship in a pneumatic throwing manner. Meanwhile, the seawater sampling valve with the engineering plastic valve core and the flow channel is innovatively designed, and the seawater sample bin and the fixing agent bin on the inner surface are coated with engineering plastic, so that the interference caused by trace element precipitation of a metal structure of the sampler in the prior art is avoided.

To suppress danger in construction work and deterioration in workability by reducing flow passage obstruction in a sewer and an influence of a large pipe diameter with respect to a fixing jig for a sensor which measures information from the pipe bottom of the sewer.SOLUTION: A fixing jig 20 for a sensor comprises an arcuate jig body 21 fitted with a water level sensor 22, guide holes 25a, 25b formed on both sides of the jig body 21, and fixtures 23a, 23b and 24a, 24b for fitting both sides to an inner wall 3a of a sewer 3. Anchor bolts 28 embedded in the inner wall 3a of the sewer 3 are inserted into through holes 27 and guide holes 25a, 25b of the fixtures 23a, 24a and fastened with nuts to fix the fixing jig 20 to the inner wall 3a.SELECTED DRAWING: Figure 2

The invention belongs to the technical field of ocean measurement, and discloses a method and a system for measuring the sea surface height of deep and far sea based on Beidou PPP-B2b. The method comprises the following steps: calculating an antenna instantaneous geodetic height of a four-antenna GNSS receiver based on a WGS84 coordinate system; correcting the attitude of the buoy by using a buoy attitude correction algorithm to obtain the height of the buoy in the vertical direction; calculating the buoy draft according to a built-in instantaneous average water depth algorithm; the sea surface instantaneous height is calculated through a sea surface instantaneous height algorithm; carrying out noise reduction processing on the calculated instantaneous height of the sea surface through a filtering calculation unit; and the final result is sent to a monitoring service platform through a data transmission module. The method not only supports ship route planning and navigation safety, helps to avoid risks, but also provides long-term, stable and reliable data support for global climate change monitoring, marine environment protection and deep sea scientific research.

The invention discloses a self-calibration and drift compensation method for an automatic underground water monitoring station, and the method comprises the following steps: 1, transmitting a reference measurement starting instruction to an underground bubble method device by an edge calculation gateway, forming a reference data pair by a bubble method water level reference value and a reference acquisition moment, and writing the reference data pair into a reference data cache region; 2, the edge computing gateway creates a state storage structure and a covariance storage structure; and step 3, the edge computing gateway reads a drift amount estimation value from the state storage structure as a drift compensation amount, and when a drift estimation standard deviation exceeds a set threshold, bubble method hardware reference acquisition is triggered. According to the invention, the problems of high manual calibration cost and lack of independent reference support in pure software estimation in the prior art are solved, so that a monitoring station can stably operate for a long time under an unattended condition and continuously output high-precision underground water level monitoring data.

The invention discloses a hydraulic engineering management and control system and method based on digital twinning, and relates to the technical field of digital twinning, and the method comprises the steps: firstly collecting and preprocessing channel condition data in real time, then comprehensively processing the data to obtain a sediment deposition factor and a congestion prediction factor, and analyzing whether sediment deposition exists according to the sediment deposition factor and the congestion prediction factor; if yes, whether the channel is congested or not is predicted according to the latter, if congestion is predicted, a congestion early warning is given out, and if no deposition exists or congestion does not exist, the process is ended correspondingly or prediction continues. The method combines flow velocity and flow direction abnormal parameters to form sediment deposition factors, bypasses underwater direct detection bottlenecks by means of digital twin modeling and simulation algorithms, improves sediment deposition judgment accuracy through multi-dimensional analysis, constructs congestion prediction factors based on a standard and actual water flow difference value and the flow direction abnormal parameters, and performs threshold exceeding early warning. The blocking risk is recognized in advance, and time is won for hydraulic engineering maintenance regulation and control.

The invention relates to the field of guide bearing bush control, in particular to a signal processing system and method for guide bearing bush clearance automatic adjustment, and the system comprises a clearance metering module, a model boundary module, a fault learning module, a clearance adjustment module and an oil film lubrication module, the model boundary module is used for establishing a dynamic pressure lubrication model of the guide bearing bush and solving the gap of the guide bearing bush, the fault learning module is used for determining the gap adjustment amount, the gap adjustment module is used for adjusting gap distribution, and the oil film lubrication module is used for adjusting lubricating oil injection. And fault identification and automatic fault-tolerant adjustment are carried out, so that mechanical vibration of the bearing is reduced, operation stability of equipment is guaranteed, abnormal bearing bush gaps are avoided, mechanical efficiency of the bearing is improved, invalid power loss is reduced, service life of the equipment is prolonged, thickness and pressure distribution of a lubricating oil film are improved, and performance of bearing turbine equipment is improved.

The invention relates to the technical field of sewage detection, in particular to a mountain spring water preparation-based water pollution detection device for water pollution control, which comprises a sample box, U-shaped connecting frames are fixedly connected to two sides of the top of the sample box, and when a cleaning part is turned over, an internal structure can be driven to filter and salvage floating objects in sewage, so that the cleaning part can be conveniently cleaned; when the cleaning piece is overturned to be in a vertical state above the sample box, the cleaning piece is in contact with the shifting piece, the cleaning piece can be shifted through an internal component of the shifting piece, so that the internal component of the cleaning piece shakes, and the salvaged floating objects fall off and fall on an impurity discharging plate; the floaters are discharged through the impurity discharging plate, so that the floaters in the sewage can be salvaged, the content of the floaters in the sewage sample is reduced, the possibility that the floaters interfere with detection during subsequent detection of the sewage sample is reduced, and the subsequent detection accuracy of the sewage sample is improved.

To provide a liquid level detection system for detecting the liquid level in a container, in which the liquid level in the container such as a water storage tank can be more widely detected compared to conventional techniques and can be applied to multiple containers.SOLUTION: A liquid level detection system for detecting the liquid level in a container comprises a vent pipe, gas supply means, pressure measurement means, and a solenoid valve.SELECTED DRAWING: Figure 1

The invention relates to the technical field of data processing, in particular to a vehicle driving state monitoring method and system based on big data, and the method comprises the steps: collecting pressure data of the bottom of a vehicle oil tank, and then selecting adjacent data segments of the pressure data, determining an abnormal factor of each piece of pressure data according to the prominence degree of each piece of pressure data relative to the adjacent data segment and the dispersion degree of the pressure data contained in the adjacent data segment, and calculating a correction coefficient of a threshold value of each piece of pressure data by comprehensively considering the abnormal factor and the data change trend of the adjacent data segment; and correcting the threshold value of the pressure data by using the correction coefficient, and carrying out anomaly detection based on the corrected threshold value. According to the method, the accuracy of abnormal detection of the pressure data is improved, and the accuracy of oil level monitoring in the vehicle running state is guaranteed.

The invention provides a multifunctional monitoring device for landslide monitoring drilling and an installation method, and belongs to the technical field of landslide engineering monitoring. The device comprises a monitoring assembly, a pipeline assembly, a data processing assembly and an auxiliary assembly; the monitoring assembly is used for monitoring landslide displacement and water level change; the pipeline assembly is used for providing a mounting space for the monitoring assembly, guiding a cable and grouting; the data processing assembly is used for collecting and processing data of the monitoring assembly; the auxiliary assembly is used for assisting installation, protection and stabilization of the monitoring device; the installation method comprises the steps of drilling, sensor customization, equipment putting, pipeline assembly connection, auxiliary assembly connection, grouting and the like, the purpose of one-hole multi-purpose ultra-deep landslide monitoring drilling is achieved, displacement monitoring can be conducted in the full hole depth, meanwhile, underground water level changes can be monitored, the measurement precision is high, the equipment manufacturing cost is low, the service life is long, and the application range is wide. The method has obvious advantages in monitoring of ultra-thick and ultra-deep landslides, and provides reliable technical support for prevention and treatment of landslide disasters.

The invention relates to the technical field of environmental monitoring, and discloses an underground water level continuous monitoring device, which comprises a monitoring probe module arranged at the bottom area of a shell and used for monitoring the water level of underground water and related environmental parameters; the data processing module is arranged in the middle area in the shell and used for collecting, processing, analyzing and storing the monitoring data; the wireless transmission module is connected with the data processing module and used for uploading the processed monitoring data to a remote monitoring system; the energy management module is arranged on the upper layer of the data processing module in the shell; the shell and installation module comprises a shell, a bottom plate and multiple layers of partition plates in the shell. Through time sequence analysis based on a long short-term memory network (LSTM), the change trend (such as water level fluctuation in the future 7 days) of the groundwater level in the future can be predicted, and through dynamic comparison of monitoring data and historical data modes, an alarm is triggered and early warning information is provided when abnormal water level changes (such as sudden drop and sudden rise) are found.

The utility model relates to the technical field of hydrological monitoring, and discloses an underground water real-time monitoring well which comprises a monitoring well. The monitoring analysis module comprises a processor, and an electronic dynamometer, a range finder and a pressure sensor which are electrically connected with the processor; the movable pulley is connected with the electronic dynamometer, the electronic dynamometer is used for measuring the stress of the movable pulley, a connecting rope is wound around the movable pulley, and one end of the connecting rope is located in the monitoring well and connected with a density ball; the hoisting mechanism is arranged on the ground surface, is electrically connected with the processor and is used for winding the other end of the connecting rope; the supporting frame is fixedly connected to the inner wall of the monitoring well, the supporting frame is located above the NAPL layer, a range finder is installed on the supporting frame and used for measuring the distance between the supporting frame and the upper surface of the NAPL layer, a telescopic rod is arranged on the supporting frame in a penetrating mode, and the lower end of the telescopic rod is connected with a pressure sensor. According to the utility model, the underground water density and the NAPL phase density can be monitored in real time by utilizing a drainage method, so that the calculation precision of the NAPL layer thickness is improved.

The utility model relates to the technical field of dam water level monitoring, and discloses a hydropower station dam water level monitoring device which comprises supporting boxes and a fixing plate, the two ends of the fixing plate are welded to the inner sides of the two supporting boxes, the front faces of the supporting boxes are provided with adjusting mechanisms and monitoring mechanisms, and each monitoring mechanism comprises a monitoring cylinder, a water level sensor, a measuring rod and a filter screen. The water level sensor is installed on the top wall in the monitoring cylinder. According to the hydropower station dam water level monitoring device, when the monitoring cylinder moves downwards, the water level sensor is inserted into water of a hydropower station dam to monitor the water level so as to measure the height of the water level, and meanwhile when the water level sensor senses hydraulic pressure, the water level sensor transmits a signal to the display device; a worker can read the reading on the measuring rod, so that the water level of the hydropower station dam is manually monitored, the interference of the external environment is reduced, and the water level is simultaneously monitored by the worker and the water level sensor, so that the accuracy of water level monitoring is improved.

This application relates to an isolated detection system and detection method for the liquid nitrogen liquid level height based on differential pressure calculation. By simulating and calculating the air pressure height difference between the liquid bottom and the liquid surface of the liquid nitrogen tank, a differential pressure signal between the return air pipe 3 and the gas measuring pipe is obtained, and the air pressure height difference between the liquid bottom and the liquid surface of the liquid nitrogen tank is calculated based on the pressure formula, so as to obtain the height position of the liquid nitrogen in the liquid nitrogen tank and perform liquid replenishment control. The differential pressure measurement system is completely isolated from the outside of the liquid nitrogen tank, eliminating the extremely harsh environment inside the tank and ensuring the long-term stable operation of the measurement equipment; the high-precision differential pressure measurement unit can accurately measure the liquid nitrogen height within the range of 1 millimeter, with high precision; only by inserting the gas measuring pipe to the lowest position of the liquid level, the detection of the corresponding range can be automatically matched without adding any circuit, and the measuring range is adjustable; it is suitable for the liquid level measurement of any sealed or unsealed tank or even a tankless situation, avoiding the short circuit of internal electronic equipment and being struck by lightning.

The utility model provides a high-precision water depth and water level measuring device suitable for large channel roughness factor calibration. The high-precision water depth and water level measuring device comprises an equipment fixing assembly, an equipment leveling assembly, a measuring instrument assembly, a wireless acquisition and transmission module and a data processing module, the equipment fixing assembly comprises a vertical measuring rod, an instrument fixer arranged at the upper part of the vertical measuring rod and two folding instrument mounting rods arranged at the lower part of the vertical measuring rod; the equipment leveling assembly is arranged on the vertical measuring rod; the measuring instrument assembly comprises a throw-in type liquid level transmitter and a single-beam underwater ultrasonic ranging sensor; a throw-in type liquid level transmitter and a single-beam underwater ultrasonic ranging sensor are mounted on the two folding instrument mounting rods respectively; the throw-in type liquid level transmitter and the single-beam underwater ultrasonic ranging sensor are respectively in communication connection with the wireless acquisition and transmission module, and the wireless acquisition and transmission module is in communication connection with the data processing module. The device can continuously measure and record the water depth and water level change process of the channel and wirelessly transmit the water depth and water level change process to a user side.

The invention discloses an air pressure liquid level meter, a liquid storage device and plant protection equipment. The first waterproof pipe is communicated with the air pressure sensor; the inner pipe diameter of the air guide pipe is larger than that of the first waterproof pipe, one end of the air guide pipe is communicated with the air pressure sensor through the first waterproof pipe, and the other end of the air guide pipe is used for extending into liquid to sense water pressure. The air guide pipe and the air pressure sensor can be communicated through the first waterproof pipe, and when external liquid enters the air pressure sensor through the end, away from the air pressure sensor, of the first waterproof pipe, the liquid easily forms a water column in the first waterproof pipe under the action of liquid tension; the water column can isolate the space between the barometric sensor and the first waterproof pipe from the outside, which is equivalent to forming plugging and preventing air between the barometric sensor and the first waterproof pipe from being discharged, and when the pressure of external liquid is balanced with the pressure of air in the first waterproof pipe, the liquid cannot continuously enter, so that the waterproofness of the barometric sensor is realized.