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41 results about "On resistance" patented technology

Water leakage point positioning method and device based on resistance gradient calculation

The invention provides a water leakage point positioning method and device based on resistance gradient calculation, and the method comprises the steps: obtaining a total resistance value and a tail end resistance value of a water leakage induction rope, and reading a preset resistivity parameter per unit length; calculating the distance of a water leakage point based on the total resistance value, the tail end resistance value and the resistivity parameter per unit length; according to the mapping relation between the length of the induction rope and the physical position established in the installation and debugging stage, the distance of the water leakage point is converted into the physical position described by corresponding 3D coordinates or characters; the physical position information is combined with real-time monitoring data to generate alarm prompt information containing a specific water leakage point location, and the alarm prompt information is output to a monitoring interface, so that accurate positioning of the water leakage point can be realized, the fault response time is remarkably shortened, and through a multi-thread data acquisition and dynamic alarm judgment mechanism, the real-time performance and the alarm accuracy of the system are improved; and the false alarm and repeated alarm frequency is reduced.
Owner:HUANENG LANCANG RIVER HYDROPOWER CO LTD

Resistor feeding mechanism on resistor assembly machine

The utility model discloses a resistor feeding mechanism on a resistor assembly machine, which comprises a positioning plate, the top of the positioning plate is fixedly connected with a lifting platform through a telescopic piece, the top of the lifting platform is symmetrically provided with vertical plates, a feeding wheel is rotatably connected between the two vertical plates, a feeding cylinder is arranged above the feeding wheel, and the feeding cylinder is connected with the lifting platform. A material guiding cylinder is welded to the top of the lifting table through a frame rod, three inclined plates are installed in the material guiding cylinder, and a buffering assembly is installed at the position, corresponding to a discharging opening in the left end of the material guiding cylinder, of the material guiding cylinder. The resistor feeding mechanism on the resistor assembly machine is reasonable in structural design and convenient to use, can adjust the feeding height so as to adapt to the station heights of different resistor assembly machines, has a relatively wide application range, can provide a relatively good buffering effect on falling resistors, can prevent the resistors falling from high positions from being damaged due to relatively large impact force, and is suitable for popularization and application. And a good use effect is achieved.
Owner:XINGTAI JIAZHENG AUTO PARTS CO LTD

Plant leaf thickness measuring instrument based on resistance feedback

The invention relates to the technical field of plant leaf measurement, and provides a plant leaf thickness measuring instrument based on resistance feedback, which comprises a main body, the main body is connected with a measuring rod through a vertical driving structure, and the bottom of the measuring rod is connected with a measuring contact through a resistance detection unit. The vertical driving structure and the resistance detection unit are electrically connected with the controller. And the blade fixing device is arranged on the main body and corresponds to the lower part of the measuring contact. Through closed-loop control combining a vertical driving structure and real-time resistance sensing, constancy of the contact pressure between the measuring head and the blade can be realized, so that manual force application errors are eliminated, excessive compression of the blade is avoided, and a high-precision, high-repeatability and lossless thickness measuring result can be obtained.
Owner:NINGXIA UNIVERSITY

Large-size and low-resistivity 4H-SiC monocrystal crystal bar and 4H-SiC monocrystal substrate

The invention discloses a large-size and low-resistivity 4H-SiC monocrystal crystal bar and a 4H-SiC monocrystal substrate, and belongs to the technical field of 4H-SiC monocrystal preparation. The thickness of the 4H-SiC single-crystal crystal bar is 15 mm or above, the resistivity of the 4H-SiC single-crystal crystal bar at any position is larger than 6 m omega.cm and smaller than 12 m omega.cm, and the resistivity variation coefficient of any cross section of the 4H-SiC single-crystal crystal bar is smaller than or equal to 5%. The 4H-SiC monocrystal crystal bar is high in thickness, lower in resistivity and more uniform in distribution, the on resistance of a power device can be remarkably reduced, and the use stability of the device is improved.
Owner:SICC SHANGHAI CO LTD

Overvoltage tuning method and system based on parallel cooperation of resistor and arc suppression coil

The invention provides an overvoltage tuning method and system based on parallel cooperation of a resistor and an arc suppression coil. The method comprises the following steps: judging an event type according to a neutral point voltage; when the event type is that the operation mode is changed, performing first tuning based on a first preset rule, and judging whether the neutral point voltage after the first tuning is greater than a threshold value or not; if the neutral point voltage after the first tuning is greater than the threshold value, performing secondary tuning based on a second preset rule, and judging whether the neutral point voltage after the secondary tuning is less than the threshold value; if the voltage of the neutral point after secondary tuning is larger than or equal to the threshold value, a second preset rule continues to be executed until the voltage of the neutral point after secondary tuning is smaller than the threshold value, and if the voltage of the neutral point after secondary tuning is smaller than the threshold value, it is judged that damping succeeds, and the resistance grounding device is reset. According to the invention, a unified zero-sequence impedance regulation and control strategy is established through cooperation of arc suppression coil operation and damping, so that the probability of occurrence of tuning overvoltage is reduced.
Owner:STATE GRID JIANGXI ELECTRIC POWER CO LTD +2

Switch device, current determination method and computer program

A load is detachably connected to a device connector of a switch device. A resistance value of a switch circuit when a sub-switch is ON is greater than an ON resistance value of a main switch. A microcomputer acquires node voltage information indicating a node voltage of a connection node located downstream of the main switch and the sub-switch from a voltage detection unit in a state where the main switch is OFF and the sub-switch is ON. The microcomputer determines whether a switch current that flows via the main switch when the main switch turns ON will be less than a current threshold value, based on the acquired node voltage information.
Owner:AUTONETWORKS TECH LTD +2

A teaching demonstration tool for resistance law

The utility model discloses a resistance law teaching demonstration teaching aid belongs to teaching aid technical field. The teaching aid includes backplate, is equipped with direct current source, electric bulb, ammeter, voltmeter and various resistances on backplate, and the both ends of each resistance are connected with resistance terminal post. The positive and negative poles of direct current source are connected with the wire with binding jaw, and the wire is connected with electric bulb and ammeter in series, and also can be connected with manual switch in series. Various resistances cover material, thickness, length, short and temperature comparison resistance, and can comprehensively show the influence of different factors on resistance. The voltmeter is used for measuring circuit voltage. Through the teaching aid, the relation between resistance and material, length, cross -section area and temperature can be directly shown, and the bright and dark of electric bulb and the change of ammeter value are matched, help student to understand resistance law, and operation is safe and convenient, and the teaching effect is improved.
Owner:CHIFENG ARCHITECTURAL ENGINEERING SCHOOL

A harness piercing crimping quality detection method based on resistance measurement

This invention relates to a method for detecting wire harness puncture and crimping quality based on resistance measurement. First, X-ray imaging is used to select samples of various defects and qualified products. The resistance values ​​of these samples are measured to establish a correspondence between resistance values ​​and defects, which is then used by a computer for judgment during subsequent product testing. Next, a resistance detection system is used to test the resistance of a group of wire harnesses, obtaining the parallel resistance values ​​of multiple wires. Using Ohm's law and the series-parallel relationship of resistances, the resistance value of a single wire in the product under test can be obtained. This value is then compared with a comparison threshold set in the computer to quickly determine whether the product under test is qualified or its defect type. A robotic arm then removes and discards unqualified products. Compared to existing X-ray imaging methods, this method significantly improves detection efficiency.
Owner:ZHEJIANG SCI-TECH UNIV

Connector and motor

The utility model discloses a connector and a motor, and the connector comprises a housing which is provided with an accommodation cavity and a terminal groove communicated with the accommodation cavity; the terminal is suitable for penetrating through the accommodating cavity and extending into the terminal groove; the resistor piece is located in the containing cavity, and the two ends of the resistor piece are connected with the terminals. According to the connector provided by the utility model, the resistor is integrated in the connector, extra components such as insulated wires, heat-shrinkable sleeves and ribbons are not needed, the overall production cost of the connector is reduced, the number of connecting points is reduced due to the integrated design, the risk of poor contact is reduced, and the reliability of the connector is improved. The influence of the external environment on the resistor is avoided, the reliability of the connector is improved, the steps of external welding, heat-shrinkable sleeve protection and the like are reduced, and the assembly process is greatly simplified.
Owner:HUAIAN WELLING MOTOR MFG

Diagnosis method and system for inter-turn short circuit of double water internally cooled generator rotor based on resistance method

The application discloses a method and system for diagnosing a turn-to-turn short circuit of a double-water internally-cooled generator rotor based on an intelligent resistance method.The method comprises the following steps: collecting rotor voltage, rotor current, rotor total water inlet flow rate, rotor total water inlet temperature and rotor total water outlet temperature sample parameters, and calculating a rotor resistance value; taking the rotor total water inlet flow rate, the rotor total water inlet temperature and the rotor total water outlet temperature as input quantities, taking the rotor resistance as an output quantity, submitting the sample to a machine learning model training, and obtaining a trained model; obtaining real-time values of the rotor voltage, the rotor current, the rotor total water inlet flow rate, the rotor total water inlet temperature and the rotor total water outlet temperature, and calculating a real-time value of the rotor resistance value; taking the real-time values of the rotor total water inlet flow rate, the rotor total water inlet temperature and the rotor total water outlet temperature as input quantities, inputting the trained model, and obtaining a rotor resistance fitting value through prediction; calculating a deviation value between the real-time value and the fitting value of the rotor resistance, determining whether the rotor has a turn-to-turn short circuit according to the deviation value, and marking a turn-to-turn short circuit severity.The method has low implementation difficulty, and the diagnosis result is accurate and reliable.
Owner:HUAQIAO UNIVERSITY

Device and method for measuring penetration depth of drilling and completion fluid into rock core based on resistance test

The invention provides a device and method for measuring the depth of drilling and completion fluid invading into a rock core based on resistance testing. The device for measuring the depth of drilling and completion fluid invading into the rock core comprises a shaft drilling and completion fluid flowing simulation module, a drilling and completion fluid invading simulation module, a temperature and pressure control module, a resistance measuring module and a recovery module. The shaft drilling and completion fluid flowing simulation module, the drilling and completion fluid invasion simulation module and the recovery module are connected in sequence; the drilling and completion fluid invasion simulation module is connected with the temperature and pressure control module and the resistance measurement module. The device can truly simulate the dynamic invasion process of the well drilling and completion fluid in the underground high-temperature and high-pressure environment to the reservoir when the well drilling and completion fluid flows, performs non-destructive measurement by using the resistance measuring instrument, realizes accurate quantitative determination of the depth of the drilling and completion fluid invading the rock core, and is suitable for deep oil and gas reservoir drilling and completion fluid pollution evaluation and reservoir protection.
Owner:SHANGHAI BRANCH CHINA OILFIELD SERVICES

HEMT device

According to the HEMT device provided by the invention, the N-type doped semiconductor adjusting layer and / or the P-type doped semiconductor adjusting layer are / is arranged, and the doping polarity, the doping concentration and the thickness can be controlled, so that the 2DEG concentration can be accurately regulated and controlled, the electric field regulation and control capability can be improved, gradient electric field distribution can be realized, and the balance between on resistance (Ron) and breakdown voltage (BV) can be realized; electric leakage and surface defects can be reduced; the dual functions of a protection layer and a field plate are realized; good processing compatibility is realized; the structure design space is higher; and the performance and the reliability of the device can be improved.
Owner:SILERGY SEMICON TECH (HANGZHOU) CO LTD

Electric washing timer

The utility model provides an electric washing timer which comprises a shell, a movable reed, a left fixed reed and a right fixed reed, the movable reed, the left fixed reed and the right fixed reed are arranged in the shell, a switching mechanism is further arranged in the shell and comprises a program switching plate, the program switching plate is provided with a pair of abutting surfaces, and the abutting surfaces elastically abut against the left fixed reed and the right fixed reed respectively. The device is characterized in that the contact surface comprises an upper straight line segment, a lower straight line segment and an inclined segment connecting the upper straight line segment and the lower straight line segment; the switching mechanism further comprises an adjusting shaft, the adjusting shaft is movably matched with the program switching plate, the program switching plate can be moved up and down by rotating the adjusting shaft, and the abutting positions of the left fixed reed and the right fixed reed on the abutting face are adjusted. The left fixed reed and the right fixed reed of the washing timer can elastically abut against any position on the inclined section, so that various washing programs can be set on the inclined section, and the situation that interference or not-in-place abutting occurs when the washing programs are added through a step-shaped abutting face in the prior art is avoided.
Owner:DONGHAI TIMER YINXIAN COUNTY +1

Low on-resistance SJ MOSFET devices

The utility model discloses a SJ MOSFET device of low on resistance, include: epitaxial layer, epitaxial layer longitudinal is equipped with at least two first conductive type column and at least one second conductive type column, and first conductive type column and second conductive type column interval arrangement, at least two gate grooves, and gate groove is located respectively on epitaxial layer and is located on first conductive type column upper portion correspondingly, at least two connecting holes, and at least two connecting holes interval are located between two gate grooves, SJ MOSFET device of low on resistance of the utility model is equipped with multiple connecting holes between gate groove, can reduce the distance between gate groove and connecting hole, has reduced on resistance, has promoted the reliability of device.
Owner:HEFEI SIPU SEMICON TECH CO LTD

Semiconductor device having a high breakdown voltage and a low on resistance, and method for manufacturing the same

A semiconductor device includes a semiconductor layer, a drift region formed in the semiconductor layer, and a dielectric film formed in the drift region. The drift region includes a first side well, a second side well and a well stack. The first side well has a first type conductivity. The second side well has the first type conductivity. The well stack is disposed laterally between the first side well and the second side well, and includes a plurality of intermediate wells that are stacked from top to bottom. A topmost one of the intermediate wells has a second type conductivity opposite to the first type conductivity, and covers bottom and side surfaces of the dielectric film. Two adjacent ones of the intermediate wells have different type conductivities.
Owner:TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

Time domain inter-turn protection method and system for reactor based on impedance parameter identification

A time-domain inter-turn protection method and system for reactors based on resistance and inductance parameter identification is proposed. This method obtains the instantaneous values ​​of the three-phase currents at the beginning and end of the reactor within a sliding window. A current matrix is ​​constructed using the instantaneous values ​​of the three-phase currents at the beginning and their rate of change. The instantaneous voltage across the neutral point reactor is calculated based on the inductance value of the small reactor at the neutral point and the rate of change of the instantaneous value of the self-generated zero-sequence current at the end of the reactor within the sliding window. A voltage vector is constructed using the voltage difference between the instantaneous voltage across the reactor within the sliding window and the instantaneous voltage across the small reactor at the neutral point. The equivalent resistance and equivalent inductance of the reactor are calculated using the current matrix and voltage vector. When the equivalent resistance is greater than a resistance threshold and the equivalent inductance is less than an inductance threshold, and this condition persists for a set duration, an inter-turn fault triggers the protection action. The protection method exhibits high sensitivity and is reliable even when the reactor core is saturated, the line distributed capacitance is high, or the reactor oscillates, without malfunctioning. It is also unaffected by new power systems.
Owner:NARI TECH CO LTD +2

Photovoltaic module power supply method based on resistance difference circuit break protection and structure and application thereof

The invention relates to a power supply method of a photovoltaic module based on resistance difference circuit break protection and a structure and application thereof. The power supply method comprises the steps that when a sub-battery breaks down, a bypass conduction band provides a bypass, so that current bypasses the sub-battery which breaks down, and the other sub-batteries work normally; the sub-cell is prepared from a perovskite cell through laser cutting; and the resistance ratio of the bypass conduction band to the sub-battery is 200 times. The technical problem to be solved is how to provide a power supply method for a photovoltaic module capable of reducing the voltage drop of series resistors.
Owner:CNNC OPTOELECTRONICS TECH (SHANGHAI) CO LTD

Metal film thickness measuring method based on resistance method

The invention belongs to the technical field of film material measurement, and particularly relates to a metal film thickness measurement method based on a resistance method. According to the method, a plurality of groups of standard films with different thicknesses and corresponding electrodes are integrally prepared on a single substrate at one time, so that high consistency of all standard samples on the substrate, the electrodes, the deposition process and the surface area is ensured, and system errors caused by sample differences in a traditional dispersion calibration method are greatly eliminated; the established resistance-thickness standard curve is more accurate and reliable; in the whole measurement process, resistance measurement is carried out through the electrode which is prepared in advance and integrated with the thin film, and an external measurement probe is only in contact with the electrode, so that direct mechanical contact with the surface of the fragile metal thin film is completely avoided, the problems of contact damage and errors caused by contact resistance are thoroughly solved, and the method belongs to real nondestructive detection; the measurement error can be controlled within 10%; complicated and expensive special test equipment is not needed, the operation process is simple and convenient, and the method is easy to popularize in industrial circles and laboratories.
Owner:QUANZHOU NORMAL UNIV

Negative resistor based on resistor-capacitor alternating current coupling bias and application thereof

The invention discloses a negative resistor based on resistor-capacitor alternating current coupling bias, the negative resistor is formed by cross coupling connection of MOS tubes, the bias voltage is isolated from the actual input voltage by using a resistor-capacitor alternating current coupling bias mode, the bias precision and stability are significantly improved, the overall performance of the negative resistor is further enhanced, and the mismatch effect is inhibited. In addition, negative resistor work is directly carried out without source electrode degeneration, so that the power consumption of the negative resistor is greatly improved, high energy efficiency is realized, and the structure is obviously superior to that of a traditional structure.
Owner:ZHEJIANG UNIV

High-voltage load resistor rack and load box

The utility model provides a kind of high pressure load resistance shelf and load box.High pressure load resistance shelf includes resistance fixing device and the resistance module installed on resistance fixing device.Resistance module includes at least two groups of resistance branch and at least three groups of output terminal.At least two groups of resistance branch and at least three groups of output terminal are electrically connected, and at least two groups of resistance branch include multiple parallelly connected resistances.At least two groups of resistance branch are connected in series / parallel, to realize multi-grade resistance value output.Compared with prior art, the utility model can obtain multi-grade resistance value by the series connection or parallel connection combination between different resistance branch, and the output terminal outputs different resistance value, meets the test demand of high voltage power supply under different load conditions, and provides more comprehensive test result.
Owner:SUZHOU XWC ELECTRONIC TECH CO LTD

Semiconductor device

PendingCN121359606ADevice materialJFET
In a trench MOSFET having a vertical channel fin structure, the turn-on resistance is reduced while ensuring short-circuit tolerance. A semiconductor device (1) is provided with: a plurality of trenches (2) arranged in a second direction and having a long side direction in a first direction and a short side direction in the second direction in plan view; a first source region (3) of a first conductivity type, at least a portion of which is partitioned by the plurality of trenches (2); and a channel region (5) of a second conductivity type that is in contact with the lower surface of the first source region (3) and is partitioned by a plurality of trenches (2), the channel region (5) being connected to the body region (9) and in which a channel current flows in the vertical direction, the length in the first direction of a gate electrode (7) disposed inside the trenches (2) being longer than the length in the first direction of a JFET region (8), and the length in the second direction of the JFET region (8) being smaller than the length in the first direction of the gate electrode (7). The impurity concentration of the JFET region (8) is higher than the impurity concentration of the drift region (10), and the dimensions of the body region (9) and the JFET region (8) in the depth direction from the lower portion of the trench (2) are both greater than 0.5 [mu] m.
Owner:HITACHI POWER SEMICON DEVICE LTD

High-power thick-film resistor

The utility model relates to the technical field of resistors, and discloses a high-power thick-film resistor which comprises a resistor body, a rectangular groove is formed in the upper end of the front surface of the resistor body, a replacement mechanism is arranged in the rectangular groove and comprises a connecting block and two screws, the connecting block is installed in the rectangular groove in a sliding mode, and the two screws are arranged in the rectangular groove. Two pins are fixedly connected to the front surface of the connecting block, two threaded grooves are formed in the upper surface of the connecting block, the two screws are installed in the two threaded grooves in a threaded mode, and through the arrangement of the connecting block and the two screws, the two screws can be rotated, so that the connecting block and the pins are detached from the interior of a rectangular groove in the resistor body; according to the high-power thick-film resistor provided by the utility model, the two pins can be replaced, so that after the high-power thick-film resistor is welded for multiple times, the two pins can be replaced, the thick-film resistor keeps relatively good weldability, and the use efficiency of the high-power thick-film resistor is improved.
Owner:SHENZHEN LI KUN TECH CO LTD

Film strain gauge for temperature compensation based on parting structure resistor and manufacturing method thereof

The invention discloses a multi-layer film strain gauge for compensating temperature based on a Peano parting structure and a manufacturing method thereof, and belongs to the technical field of fault monitoring of thermal structure components of aircrafts. The strainmeter structurally comprises a substrate, an adhesive insulating layer, a sensitive layer, a protective layer and a lead in sequence from bottom to top, the sensitive layer pattern is composed of a strain gauge pattern and a Peano parting resistor pattern. According to the invention, different pattern structures prepared from the same material have different strain response capabilities, and a novel strain gauge which is not interfered by temperature can be obtained. Due to the fact that the Peano parting structure resistor is of a multi-section arc-shaped structure, the Peano parting structure resistor has deformation compensation performance when affected by strain, and the GF value of the Peano parting structure resistor is far lower than that of a strain gauge made of the same material. After the strain gauge made of the same material and the Peano parting structure resistor are combined, the strain gauge and the Peano parting structure resistor have the same TCR and different GFs, the influence of the TCR on the resistor can be eliminated by measuring the resistance of the strain gauge and the Peano parting structure resistor at the same time or a Wheatstone half-bridge structure formed by the strain gauge and the Peano parting structure resistor, and therefore decoupling of the temperature / strain-resistance relation is achieved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Biosensor based on resistance adjustment and automatic coding method thereof

The invention discloses a biosensor based on resistance adjustment, the biosensor comprises an insulating base plate and an electrode system located on the insulating base plate, the electrode system comprises a first electrode, a second electrode, a third electrode and a fourth electrode, a series of fan-shaped large-resistance wires which are increased continuously are connected between the first electrode and the second electrode, and the first electrode is connected with the second electrode. The large-resistance wires are connected in a series, the large-resistance wires with specific lengths are connected between the third electrode and the fourth electrode, and the first electrode, the second electrode, the third electrode and the fourth electrode are sequentially provided with a first contact disc, a second contact disc, a third contact disc and a fourth contact disc which can be connected with a tester. Under the condition that other testing functions are not affected, the fourth contact disc can be combined with the first contact disc or the second contact disc. The invention belongs to the technical field of biosensors, and particularly relates to a biosensor based on resistance adjustment.
Owner:陈大刚

SiC power device with low on-resistance and low thermal resistance and preparation process

The invention relates to the technical field of semiconductors, in particular to a SiC power device with low on resistance and low thermal resistance and a preparation process. Comprising an N + substrate and an N-epitaxial layer which are sequentially arranged from bottom to top; the N-epitaxial layer is provided with a plurality of JFET (Junction Field Effect Transistor) regions which respectively extend downwards from the top surface of the N-epitaxial layer, and the downward extending depth of the JFET regions is smaller than the thickness of the N-epitaxial layer; the plurality of P type base regions are respectively connected with the JFET region; the P + region is positioned at the side part of the P-type base region, and the depth of the P + region is equal to that of the P-type base region; the N + regions extend downwards from the top surface of the P-type base region, and the depth of the N + regions extending downwards is smaller than that of the P-type base region; the resistance and the thermal resistance of the whole substrate layer can be remarkably reduced, so that the on resistance of the silicon carbide power device is reduced, the heat dissipation performance is improved, and the energy efficiency and the reliability of the device are improved.
Owner:YANGZHOU JIEGUAN MICROELECTRONICS CO LTD

Plastic water supply pipeline leakage monitoring and early warning method and equipment based on resistance and capacitance

The invention relates to a plastic water supply pipeline leakage monitoring and early warning method and equipment based on resistors and capacitors, and belongs to the technical field of water supply pipeline leakage monitoring. Two parallel conductive plastic fusion bodies extending along the length of the pipeline are formed on the surface of the plastic pipeline body through a forming process; resistance and capacitance detection terminals are arranged on the pipeline at intervals, three electrodes are arranged to be electrically connected with the two independent conductive plastic fusion bodies at the position respectively, and a grounding electrode is connected with the ground. The device is used for detecting the change conditions of capacitance and resistance between two conductive plastic fusion bodies and between each conductive plastic fusion body and the ground in real time, setting a capacitance early warning threshold value and a resistance early warning threshold value, judging pipeline leakage when one capacitance increment exceeds the early warning threshold value and one resistance decrement exceeds the early warning threshold value, and judging pipeline leakage when the other capacitance increment exceeds the early warning threshold value and the other resistance decrement exceeds the early warning threshold value. And triggering alarm. The problems of high omission ratio, high cost, poor stability and the like in the prior art are solved, and an efficient solution is provided for water supply network leakage treatment.
Owner:SHANDONG FENGSHI INFORMATION TECH CO LTD

Phase-adjustable annular voltage-controlled oscillator based on resistance feedforward

A phase-adjustable annular voltage-controlled oscillator based on resistance feedforward comprises four differential current starvation type delay units which are identical in structure and connected in a loop mode, the positive output end and the negative output end of the first differential current starvation type delay unit are connected with the negative input end and the positive input end of the second differential current starvation type delay unit respectively, and the first differential current starvation type delay unit is connected with the second differential current starvation type delay unit. The positive and negative output ends of the second, third and fourth differential current starvation type delay units are respectively connected with the positive and negative input ends of the third, fourth and first differential current starvation type delay units to form a main path loop; the positive and negative output ends of the first and fourth differential current starvation type delay units are respectively connected with the positive and negative feed-forward ends of the third and second relative differential current starvation type delay units; the positive and negative output ends of the second and third differential current starvation type delay units are respectively connected with the negative and positive feed-forward ends of the fourth and first relative differential current starvation type delay units to form a feed-forward path loop; and each differential current starvation type delay unit is additionally provided with bias voltage ends of a PMOS (P-channel Metal Oxide Semiconductor) transistor and an NMOS (N-channel Metal Oxide Semiconductor) transistor. According to the invention, through the resistor feed-forward structure, the output frequency of the oscillator is integrally improved, the resistance value of the feed-forward resistor is adjusted through the control word, a GHz-level clock signal is output, and the oscillator has a relatively wide frequency adjustment range, can be used for initial deflection calibration of phase mismatch among multiple channels in a multi-phase clock application scene, and is beneficial to reducing the calibration cost.
Owner:SHANGHAI JIAOTONG UNIV

A method for monitoring damage of a silicon carbide matrix composite based on resistance change

The present application relates to a kind of silicon carbide matrix composite damage monitoring methods based on resistance change, belong to composite damage monitoring technical field, the probability model of fiber failure in the resistance model composite is coupled to obtain composite damage monitoring model, the damage state of composite is monitored and evaluated in real time based on the composite damage monitoring model, ensure the service safety and reliability of composite, effectively predict the remaining useful life of composite, prevent the occurrence of catastrophic failure.
Owner:BEIHANG UNIV

Multi-cavity synchronous automatic material feeding and blocking device

The utility model provides a kind of multi-cavity synchronous automatic material placing repair resistance device, it is related to repair resistance device technical field, including resistance meter, the front end of resistance meter is provided with robot, the side of robot is connected with vibrating disk, the surface of resistance meter is provided with multiple groups repair resistance cavity equidistantly, the upper end of each repair resistance cavity is provided with pressure compensation component.In the utility model, after robot places each group of products in vibrating disk in repair resistance cavity, resistance meter will automatically promote test probe to the surface of product close, reach the purpose of pressure compensation by the elastic force of spring, the elastic force of spring can continuously act on resistance test probe, so that it is always closely attached to product surface, even in the existence of tiny unevenness on product surface or slight vibration during equipment operation, good contact can be guaranteed, so as to avoid the detection error caused by loose contact, improve the accuracy of detection.
Owner:FOSHAN HAOYUN ELECTRICAL APPLIANCE ACCESSORIES CO LTD