CN108259049A - The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization - Google Patents
The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization Download PDFInfo
- Publication number
- CN108259049A CN108259049A CN201810037958.6A CN201810037958A CN108259049A CN 108259049 A CN108259049 A CN 108259049A CN 201810037958 A CN201810037958 A CN 201810037958A CN 108259049 A CN108259049 A CN 108259049A
- Authority
- CN
- China
- Prior art keywords
- signal
- detectable signal
- pipeline
- emitter
- solid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 22
- 238000012360 testing method Methods 0.000 claims abstract description 8
- 230000001360 synchronised effect Effects 0.000 claims abstract description 6
- 230000005611 electricity Effects 0.000 claims description 3
- 238000001514 detection method Methods 0.000 abstract description 29
- 230000005540 biological transmission Effects 0.000 abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 4
- 230000002787 reinforcement Effects 0.000 abstract 1
- 238000005260 corrosion Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000003628 erosive effect Effects 0.000 description 3
- 210000001367 artery Anatomy 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 210000003462 vein Anatomy 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 1
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 230000011664 signaling Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/02—Transmitters
- H04B1/04—Circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/185—Space-based or airborne stations; Stations for satellite systems
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Astronomy & Astrophysics (AREA)
- Aviation & Aerospace Engineering (AREA)
- General Physics & Mathematics (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
The buried and underwater metallic conduit detectable signal emitter and detection method of satellite synchronization solve the problems, such as that great burying, long span are buried and pass through metallic conduit detectable signal because attenuation causes signal strength and transmission range that cannot meet detection and require under water.The emitter includes 4 solid-state relays in parallel again of connecting two-by-two of signal transmitter, control circuit and its control, and the intermediate node of two solid-state relays is drawn as two signal output ends, and a ground connection, one connects pipe under test.Output detectable signal stringent synchronization in sequential is realized by receiving GPS second pulse signal, two emitters is enable to realize fully synchronized superposition to the detection electric current that pipeline applies, reach the mutual reinforcement in transmission process of the detection electric current on pipeline, so as to increase the intensity of detectable signal, increase the effective detecting depth and distance to pipeline, so as to fulfill the detection purpose to great burying, long span crossing pipeline.
Description
Technical field
The present invention satellite synchronization direct impulse sender unit, be related to great burying underground metal pipes route exploration and
The superposition of buried depth measuring signal belongs to the applied technical field of buried and underwater metallic conduit detection.
Background technology
By residing for the underwater crossing pipeline such as the pipeline and rivers of Directional Drilling for Pipeline Crossing, lake being one special
Long span, great burying environment, during detecting its routing and measuring buried depth, need to apply to pipeline to be detected sufficiently strong
The probe current signal of degree.If accurately cannot implement to position to buried and underwater crossing pipeline, corrosion and protection situation etc. its
Its Corrosion monitoring just can not effectively be implemented.
Generally conventional land detectable signal applying method is：
1. earth polar method：Signal transmitter is set up in pipeline one end, one end output line of signal transmitter is connect with pipeline, separately
One output terminal is connect with earthing pole.The current signal of transmitting is made to pass through earthing pole, greatly form conduction with pipeline corrosion protection layer surface
Loop transfer.The insulation of the transmission range and quality of probe current signal and the conductivity degree, pipeline external anti-corrosion layer of soil environment
The resistance in transmission circuit that the factors such as performance and integrated degree determine is related.When soil conductivity is poor, erosion resistant coating insulation performance is poor,
When erosion resistant coating integrity degree is low, the signal code of pipeline can be applied to regard to small, transmission range is with regard to short；Conversely, signal transmission distance
It is then remote.
2. circuit connection method：For avoid environment influence, improve detectable signal current strength, pipe ends directly with transmitting
Machine is connected, and pipeline and transmitter itself output line is made to form current supply circuit.If erosion resistant coating is appropriate, signal is lost in seldom, signal
Intensity and transmission range can all increase substantially.
For the underground of directional drilling crossing, submarine pipeline, earth polar method limited transmission distance, circuit connection method environment item
Part is limited；It is the effective ways of both replies limitation by the addition method for respectively applying signal at detection section both ends.
Invention content
It is buried and pass through metallic conduit detectable signal because attenuation causes under water the present invention seeks to solve great burying, long span
Signal strength and transmission range cannot meet the problem of detection requires, and provide a kind of buried and underwater metallic conduit of satellite synchronization
Detectable signal emitter and applying method.Present invention is mainly applied to great burying, long span is buried and passes through metal tube under water
Route exploration, the buried depth in road measure.
Technical scheme of the present invention
1st, the buried and underwater metallic conduit detectable signal emitter of satellite synchronization
Emitter includes signal modulation unit, control circuit and satellite pulse per second (PPS) receiving unit.In signal modulation list
Two solid-state relay branches of parallel connection between two current signal output ends in member, each each series connection in solid-state relay branch road
Two solid-state relays, 4 solid-state relays, the intermediate node of two solid-state relay branches is drawn as two letters altogether
Number output terminal, a ground connection, one connects pipe under test, the satellite second arteries and veins that 4 solid-state relays are connected by control circuit according to it
The synchronizing signal of receiving unit acquisition is rushed, break-make control is carried out according to the sequential of setting, is visited so as to fulfill buried and submarine pipeline
Survey the modulation and transmitting of signal.
The concrete methods of realizing of emitter is：
1) pps pulse per second signal of satellite broadcasting is received by satellite pulse per second (PPS) receiving unit, it can be to the onboard clock of transmitter
Accurate calibration is carried out, avoiding the problem that the current signal of work at a distance two transmitter transmittings cannot synchronize for a long time.It defends
Two sender units that star synchronizes can send the detectable signal of stringent synchronization for a long time, in synchronization to same target
The signal strength of application can realize synchronous superposition.
2) using microprocessor as the control circuit of core, by controlling the orderly break-make of 4 solid-state relays, by direct current
The electric current in source is modulated into the DC pulse signal of setpoint frequency, is applied on pipeline to be detected, realizes great burying, long leap
The route exploration and buried depth of pipeline measure.
3) the DC pulse current signal with positive-negative half-cycle that can be exported simultaneously can eliminate detectable signal to pipeline the moon
Protect the influence of polarization potential in pole.
2nd, the applying method of detectable signal is carried out using above-mentioned detectable signal emitter, step is as follows：
1) an above-described detectable signal emitter, detectable signal transmitting are respectively set up at the both ends of pipeline to be detected
The signal output end ground connection of device, another signal output end are connected to one end of pipe under test；
2) two detectable signal emitters receive the pulse per second (PPS) of satellite broadcasting by satellite pulse per second (PPS) receiving unit respectively
Signal to carry out accurate calibration to the onboard clock of emitter, avoids what work at a distance two emitters emitted
The problem of current signal cannot synchronize for a long time enables two sender units of satellite synchronization to send for a long time strictly together
The detectable signal of step；
3) in satellite synchronous signal precision up to 10-6It is detected during the second, so as to ensure two emitters in synchronization
Strictly synchronous superposition can be realized to the current signal that same target applies, is effectively increased the intensity and range of detectable signal,
Route exploration and depth survey so as to fulfill great burying crossing pipeline.
Detection principle of the present invention and calculation basis：Based on satellite pps pulse per second signal, using microprocessor as the control electricity of core
Road by controlling the orderly break-make of 4 solid-state relays, by the output current of DC power supply, is modulated into the direct current of setpoint frequency
Pulse signal, ensures accurately consistent in same time signal output amplitude, direction, passes through transmitter erection mode and realizes common make
Used time is superimposed forward or backwards.
Transmitter frequency and a wavelength time relationship：
F-frequency, unit Hz；
The wavelength time of t-mono- complete cycle, μ s.
During in order to improve receiving unit to the inductive effects of signal and the triggering of guarantee solid-state relay and the response disconnected
Between, certain interval delay is introduced between the positive and negative half-wave of signal, the duration of delay is reached most with the reception characteristic of detection unit
It is excellent to determine.
The advantages of the present invention：
It is buried and underwater pass through metallic conduit positioning and corrosion and protection detection engineering that the present invention is applied to great burying.It visits
The technical parameter of amount includes：The routing of pipeline and buried depth.In great burying, long span is buried and during underwater crossing pipeline detection, such as
Fruit earth polar method, which applies signal, cannot effectively cover the half of detected duct length, and applying signal respectively at both ends can not complete
Whole pipeline section Detection tasks of detected pipeline.Using the method for the present invention in the both ends test pile (or end of being unearthed) for being detected pipeline
A transmitter is respectively set up, while signal is applied to detected pipeline, valid analysing range is individually to set up one at both ends originally
1.5~2.0 times of the sum of platform transmitter valid analysing range.
It is buried and pass through metallic conduit signal strength detection under water great burying can be effectively improved using the present invention, change with
Past signal applies pattern, by ground receiver or the detection device being mounted on submarine pipeline detection robot ROV, realizes
Route exploration and buried depth to underwater crossing pipeline measure.
The present invention integrates the technologies such as signal modulating method, computation model, applying mode.In technical method and composition
Signal applying mode has that device structure is simple, be easy to make, easy to use, detectable signal is stackable, effective detecting distance adds
The advantages that long.When in pipeline one end earth polar method plus signal, it is whole that signal quality is unsatisfactory for detection pipeline, but effectively detection away from
From more than pipeline section overall length 1/4~1/3 when, can use the present invention emitter give pipeline apply detectable signal.
Description of the drawings
Fig. 1 is emitter control structure figure；
Fig. 2 is the control principle drawing of emitter；
Fig. 3 is modulation afterpulse signal timing diagram；
Fig. 4 is ROV submarine pipelines detection schematic diagram；
Fig. 5 is 640Hz alternating impulse signal timing diagrams.
In figure, 1 represents emitter, and 2 represent satellite antenna, and 3 represent crossing pipeline, and 4 represent underwater detection equipment, 5 tables
Show test pile, 6 represent detection operations lash ship.
Fig. 2 is the realization principle figure of Fig. 1, and the connection mode of a solid-state relay, other 3 connection sides are only drawn in figure
Formula is identical.
【Specific embodiment】
1st, hardware realization：
The buried and underwater metallic conduit detectable signal emitter of satellite synchronization, including signal modulation unit, control electricity
Road and satellite pulse per second (PPS) receiving unit.Parallel connection two is solid between two current signal output ends in signal modulation unit
State relay branch, each two solid-state relays of series connection in each solid-state relay branch road, 4 solid-state relays altogether, by two
The intermediate node of a solid-state relay branch is drawn as two signal output ends, a ground connection, and one connects pipe under test, 4
The synchronizing signal that the satellite pulse per second (PPS) receiving unit that solid-state relay is connected by control circuit according to it obtains, according to setting when
Sequence carries out break-make control, so as to fulfill buried and submarine pipeline detectable signal modulation and transmitting.Wherein,
1) power supply.Using external 12V~24V storage battery power supplies, can concatenate, up to 96V.
2) modulation of alternating impulse electric current signal.Transmitter circuitry control principle drawing (such as Fig. 2), the second arteries and veins in control circuit
It rushes receiving unit and pps pulse per second signal, the internal clocking of timing alignment MCU is received by satellite antenna, MCU passes through solid-state relay
Control circuit is by setting sequential break-make, by the D.C.current modulation of input into the pulse signal (such as Fig. 3) of alternation.
2nd, detection method is realized：
First, normally apply signal, detectable signal quality, if signal covers to pipeline in crossing pipeline one end earth polar method
It is whole that lid quality cannot meet detection pipeline, but when effectively detecting distance is more than the 1/4~1/3 of target area interior conduit overall length,
The emitter of the present invention can be used to apply signal using earth polar method.
Second step respectively sets up a detectable signal emitter, two transmitting dresses in pipe ends to be detected earth polar method
The signal output end positive and negative anodes reversal connection put, GPS antenna is connected on emitter, enabling signal emitter, is selected same
Frequency treats that pulse per second (PPS) receiving unit searches star success, and emitter can export pipeline the detectable signal of stringent synchronization, make two
The signal of end transmitting realizes superposition.
Third walks, and land detection along pipeline search, checking signal quality and is implemented to detect.
The detection method of underwater through section is identical：Two positions that can apply signaling point of pipeline are first determined on the bank on both sides,
Using the pipeline section of point-to-point transmission as target area, ROV is launched to target area and carries out signal tracing and detection, whole section is completed and passes through
The detection (such as Fig. 4) of pipeline.
【Case is embodied】
1. timing Design.640Hz is used for great burying detectable signal frequency.
Calculate sequential：Detectable signal frequency f=640Hz, is=1562.5 μ s the time required to a complete signal, during half-wave
Between 0.5t=781 μ s.Relay triggering 0.1 μ s of the response time disconnects corresponding 0.9 μ s of time.Control sequential is in addition to vacating solid-state
Outside the response time of relay, consider that receiving unit induction of signal effect is optimal, 480 μ s is selected to lead to, 301.25 μ s break.
Specific control sequential：Positive half-wave connects 480 μ s → 301.25 μ s of disconnection → negative half-wave and connects 480 μ s → 301 μ of disconnection
S completes a cycle.(Fig. 5)
2. component selects.MCU control chips STM32F103CB, GPS module and antenna, optocoupler-TLP187 (transistors
Export optocoupler), N-MOSFET-SKM180A020 (MOSFET modules), isolated power supply module-DCP021212.Power supply selection by
The 48V that 12V is composed in series is battery-powered.
3. control program：
4. implementation result
The emitter of satellite synchronization pipeline detection is successfully realized using as above parameter.The device is wide by about 700
At the both ends of pipeline to be detected, earth polar method respectively sets up an emitter, the signal of two emitters respectively for the river both sides of rice
Output positive and negative charge reversal connection.Using the external storage battery power supply of 12V, actual transmission as a result, 2.34 amperes of the emission current of one,
Another transmitting signal code is 1.91 amperes, and in river centre position, it is 1.77 amperes to measure synchronizing signal electric current on pipeline,
The coordinate detection and buried depth for realizing 17.5 meters of deep pipelines measure.
Claims (2)
1. a kind of buried and underwater metallic conduit detectable signal emitter of satellite synchronization, including signal modulation unit, control
Circuit and satellite pulse per second (PPS) receiving unit；It is characterized in that, two current signal output ends in signal modulation unit it
Between two solid-state relay branches in parallel, each two solid-state relays of series connection in each solid-state relay branch road, 4 solid-states altogether
Relay draws the intermediate node of two solid-state relay branches as two signal output ends, a ground connection, a reception
Test tube road, the synchronizing signal that 4 solid-state relays are obtained by control circuit by the satellite pulse per second (PPS) receiving unit connected, according to
The sequential of setting carries out break-make control.
2. a kind of applying method that detectable signal is carried out using detectable signal emitter described in claim 1, which is characterized in that
This method comprises the following steps：
1st, a detectable signal emitter described in claim 1, detectable signal are respectively set up at the both ends of pipeline to be detected
The signal output end ground connection of emitter, another signal output end are connected to one end of pipe under test；
The pulse per second (PPS) that 2nd, two detectable signal emitter receives satellite broadcasting by satellite pulse per second (PPS) receiving unit respectively is believed
Number, to carry out accurate calibration to the onboard clock of emitter, avoid the electricity of work at a distance two emitter transmittings
The problem of stream signal cannot synchronize for a long time, enables two sender units of satellite synchronization to send stringent synchronization for a long time
Detectable signal；
3rd, in satellite synchronous signal precision up to 10-6It is detected during the second, so as to ensure two emitters in synchronization pair
The current signal that same target applies can realize strictly synchronous superposition, be effectively increased the intensity and range of detectable signal, from
And realize route exploration and the depth survey of great burying crossing pipeline.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810037958.6A CN108259049B (en) | 2018-01-16 | 2018-01-16 | The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810037958.6A CN108259049B (en) | 2018-01-16 | 2018-01-16 | The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108259049A true CN108259049A (en) | 2018-07-06 |
| CN108259049B CN108259049B (en) | 2019-07-05 |
Family
ID=62741117
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810037958.6A Active CN108259049B (en) | 2018-01-16 | 2018-01-16 | The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108259049B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114414461A (en) * | 2021-12-17 | 2022-04-29 | 中石化管道技术服务有限公司 | Protective potential satellite synchronous measurement device with positioning current pipeline and method |
| CN115166838A (en) * | 2022-09-07 | 2022-10-11 | 浙江图维科技股份有限公司 | Method and system for positioning pipeline |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1702480A (en) * | 2005-05-25 | 2005-11-30 | 淄博威特电气有限公司 | Method and apparatus for judging between right and wrong tracking and discriminating pipeline in metal pipeline detection |
| CN101571234A (en) * | 2009-06-16 | 2009-11-04 | 北京埃德尔黛威新技术有限公司 | Liquid pressure conduit leak detection device |
| US8219214B1 (en) * | 2008-03-18 | 2012-07-10 | Mimlitz James E | Supervisory control and data acquisition protocol converter |
| CN104865606A (en) * | 2015-06-05 | 2015-08-26 | 中国海洋大学 | High-effect large-current electromagnetic transmitting system and method |
| CN105353414A (en) * | 2015-10-22 | 2016-02-24 | 中国科学技术大学 | Pipeline detection method and system |
| CN107430206A (en) * | 2015-03-31 | 2017-12-01 | 富士地探株式会社 | Use the detection method and its device of the embedded metal of synchronous detection method |
-
2018
- 2018-01-16 CN CN201810037958.6A patent/CN108259049B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1702480A (en) * | 2005-05-25 | 2005-11-30 | 淄博威特电气有限公司 | Method and apparatus for judging between right and wrong tracking and discriminating pipeline in metal pipeline detection |
| US8219214B1 (en) * | 2008-03-18 | 2012-07-10 | Mimlitz James E | Supervisory control and data acquisition protocol converter |
| CN101571234A (en) * | 2009-06-16 | 2009-11-04 | 北京埃德尔黛威新技术有限公司 | Liquid pressure conduit leak detection device |
| CN107430206A (en) * | 2015-03-31 | 2017-12-01 | 富士地探株式会社 | Use the detection method and its device of the embedded metal of synchronous detection method |
| CN104865606A (en) * | 2015-06-05 | 2015-08-26 | 中国海洋大学 | High-effect large-current electromagnetic transmitting system and method |
| CN105353414A (en) * | 2015-10-22 | 2016-02-24 | 中国科学技术大学 | Pipeline detection method and system |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114414461A (en) * | 2021-12-17 | 2022-04-29 | 中石化管道技术服务有限公司 | Protective potential satellite synchronous measurement device with positioning current pipeline and method |
| CN115166838A (en) * | 2022-09-07 | 2022-10-11 | 浙江图维科技股份有限公司 | Method and system for positioning pipeline |
| CN115166838B (en) * | 2022-09-07 | 2022-12-16 | 浙江图维科技股份有限公司 | Method and system for positioning pipeline |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108259049B (en) | 2019-07-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100432703C (en) | Electromagnetic surveying | |
| CN105705956A (en) | A method of single-ended fault location in HVDC transmission lines | |
| CN110927802B (en) | Submarine cable fault accurate positioning method based on magnetic vector data and positioner | |
| CN108259049B (en) | The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization | |
| CN104618032A (en) | Electromagnetic wave transmission system crossing seawater-air interface and method thereof | |
| CN105891890A (en) | Non-contact frequency domain electrical method real-time advanced detection system and method for shield carrying | |
| CN105242321A (en) | Sea submersible horizontal orthogonal emission system and application method thereof | |
| DE2962708D1 (en) | Apparatus and method for locating sheath faults in underground power supply cables | |
| CN103984031B (en) | Ocean controllable source electromagnetic detecting transmitter underwater device and control method thereof | |
| CN103837903A (en) | Underground full-wave nuclear magnetic resonance detection device based on wireless network | |
| CN108415055A (en) | Mobile object telltale mark device in a kind of fluid pipeline | |
| US20160230544A1 (en) | Auxiliary system for use in drilling | |
| CN105203993A (en) | Underground-pipeline three-point position indicator and working method thereof | |
| CN106772642B (en) | The nuclear magnetic resonance that a kind of earth electric field excites visits water system and outdoor operation method | |
| CN203673081U (en) | Underground full wave magnetic resonance sounding detection device based on wireless network | |
| CN107430206A (en) | Use the detection method and its device of the embedded metal of synchronous detection method | |
| NL2028770B1 (en) | 5g+cmft—r time domain electromagnetic field exploration system and method | |
| CN205080739U (en) | Recovery system is put to wireless sensor node cloth under water | |
| CN105005086A (en) | Searching and detection device for cable path | |
| CN100374818C (en) | Measuring method and device for built-in length of metal pipeline | |
| AU2020264385B1 (en) | Electromagnetic exploration method using full-coverage anti-interference artificial source | |
| CN109901226B (en) | Controllable source tensor geoelectromagnetic system and control calculation method thereof | |
| CN205263307U (en) | Portable ground penetrating radar car | |
| CN205384379U (en) | Synchronous array electricity method appearance system | |
| CN108957029A (en) | A kind of float technique survey river flow velocity method of LoRa wireless location |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Building 8, No. 18 Haitai South Road, Xiqing District, Tianjin, 300384 Patentee after: Tianjin Jiaxin Technology Co.,Ltd. Country or region after: China Address before: Building 8, No. 18 Haitai South Road, Xiqing District, Tianjin, 300384 Patentee before: TIANJIN GENIUS TECHNOLOGY & ENGINEERING Co. Country or region before: China |
|
| CP03 | Change of name, title or address |