73results about How to "Good temperature compensation effect" patented technology

The invention comprises a piezoelectric baseboard and two pairs of interdigital electrodes; said interdigital electrodes are located on the piezoelectric baseboard to construct both parallel acoustic surface wave measuring channel and reference channel. It features the following: coating a sensitive film on the measuring channel; coating a temperature compensation film on the reference channel.

The invention discloses a circuit of a radio-frequency power amplifier, which comprises a bias circuit and an amplification circuit. A resistance compensating structure is designed in the bias circuit, that is, a compensating resistance is added to the bias circuit. The added compensating resistance has two functions: (1) increasing the voltage compensation of the bias circuit and reducing the dependency of the circuit on the bias voltage; and (2) enhancing the temperature compensation of the bias circuit. The change of the bias voltage or temperature causes the electric current changes of Q4 and Q5 or Q7 and Q8 of NPN tube, the change quantity of VBE of voltage generated by the electric current changes between a base electrode and a collector electrode can be compensated efficiently by the change quantity of two ends of R*1 or R*2, thereby ensuring the circuit is not sensitive to the bias voltage and the temperature.

The invention belongs to the technical field of integrated pipe gallery engineering. Disclosed is a big data visualization system and method for an underground comprehensive pipe corridor. The big data visualization system of the underground comprehensive pipe corridor comprises a video monitoring module, an environmental data detection module, a central control module, a cloud service module, a device management module, a risk assessment module, an alarm module and a display module. The big data visualization system comprises a video monitoring module, an environmental data detection module,a central control module, a cloud service module, a device management module, a risk assessment module, an alarm module and a display module. The invention establishes an Internet of Things communication framework between the security, ventilation, power supply, drainage, lighting and fire fighting equipment in the pipeline corridor and the cloud server platform through a management module, utilizes the Internet of Things technology, and greatly facilitates the management of the operation and maintenance equipment. At the same time, through the risk assessment module, the invention can construct a comprehensive pipe corridor disaster chain Bayesian network model according to the evolution law of a plurality of potential disasters in the comprehensive pipe corridor, predict the occurrence probability of each disaster in the pipe corridor and evaluate the loss degree of the pipe corridor, thereby proposing a scientific and effective comprehensive pipe corridor pregnant source chain broken disaster reduction mechanism and measures.

The invention discloses a self-calibration device and method for the loop parameters of a phase-locked loop. The self-calibration device comprises a phase frequency detector, a charge pump, a loop filter, a loop parameter correcting module and a main frequency divider. The phase frequency detector, the charge pump and the loop filter are sequentially connected. The loop parameter correcting module shares a common reference signal Fref input end with the phase frequency detector, and is connected to the loop filter. The main frequency divider is connected with the output end of the loop filter and passes through the main frequency detector to be fed back and input to the feedback input end of the phase frequency detector. The self-calibration device and method for the loop parameters of the phase-locked loop can overcome the defects that in the prior art, the area of a chip is large, manufacturing cost is high, and a temperature compensation effect is bad are overcome, and achieve the advantages of being small in chip area, low in manufacturing cost and good in temperature compensation effect.

An inner arc top thin wall strain cylinder drop-type optical fiber Bragg grating pressure sensor, belonging to the field of sensor technology, relates to a drop-type optical fiber Bragg grating pressure sensor for pressure measurement, characterized in that the inner side top of a metal thin wall inner cylinder is arc structured; both of the pressure-measuring optical fiber Bragg grating and the temperature compensating optical fiber Bragg grating are packaged in metallization; the pressure-measuring optical fiber Bragg grating is welded to the outer wall side of the metal thin wall inner cylinder axially with metal; the temperature compensating optical fiber Bragg grating is welded to the top outer side of the metal thin wall inner cylinder with metal; the pressure-measuring optical fiber Bragg grating is vertical to temperature compensating optical fiber Bragg grating to each other; two signal extraction single mode fibers are also packaged in metallization locally when passing through an optical fiber exit hole, and welded to the optical fiber exit hole with metal so as to close the optical fiber exit hole. The invention improves pressure-measuring range for a pressure sensor so as to solve the crossing sensitive problem of two Bragg gratings, which enhances operating temperature range for the sensor.

A fiber optic sensor includes at least two Fabry-Perot (FP cavities) defined by at least three partially reflecting surfaces which individually and together are capable of generating different interference spectra which are affected by temperature. One of the FP cavities is formed at an end of the sensor and includes a surface which is capable of supporting a thin film, the optical thickness of which is to be measured. The other FP cavity between the lead-in fiber and the first FP cavity thus does not include the film and can thus independently provide highly accurate temperature information for calibrating the optical length of the second FP cavity and compensation for temperature effects on measurement of the thin film supported thereon, preferably by subtraction of a calibrated temperature-dependent change in optical length of the second FP cavity from the measurement made.

The invention discloses a self-compensating concrete integrated strain gauge, which is mainly characterized in that a compensation resistor is provided on the strain gauge, the compensation resistor and the working piece form a half-bridge or full-bridge working mode, and the compensation resistor adopts a high-precision resistor with no stress output Or small grid strain gauges, which can automatically compensate the influence of temperature on the bridge and wires, overcome the difficulty that it is impossible to equip each measuring point with a compensation block and ensure that its temperature and change are consistent; it can also eliminate the influence of wire length on detection sensitivity At the same time, the reinforced fiber insulation base and flexible waterproof sealing material are used to carry out the overall waterproof sealing treatment, which not only ensures the technical requirements of the insulation resistance of the strain gauge, but also has the effect of convenient, fast, accurate and safe on-site installation. .

The invention discloses a thin film hydrogen sensor with a self-heating function and a temperature compensation function. The thin film hydrogen sensor comprises a shell, a top cover, a sensor chip and an adapter circuit board. The adapter circuit board is arranged on the bottom part of an inner cavity of the shell; the sensor chip is arranged on the adapter circuit board; a welding plate is arranged on the adapter circuit board; a terminal of the sensor chip is connected with the welding plate; an inner end of a cable penetrates through a cable hole so as to be connected with the welding plate; the sensor chip is sequentially provided with a base layer, an insulation layer, a lower-layer hydrogen resistance layer, a heating/temperature measuring layer, an upper-layer hydrogen resistance layer, a hydrogen sensitive layer and an anti-oxidation layer from bottom to top; the heating/temperature measuring layer is provided with a temperature measuring resistance wire and a heating resistance wire; the hydrogen sensitive layer is provided with a hydrogen sensitive resistance wire. According to the thin film hydrogen sensor provided by the invention, the heating resistance wire is arranged on the sensor chip, so that the sensor chip has a self-heating function; the sensor chip is packaged into a sealed inner cavity of the shell, so that a temperature compensation function is conveniently improved, and the measurement accuracy is improved; through arranging the adapter circuit board, the thin film hydrogen sensor is convenient to apply.

Provided is a method for manufacturing an acoustic wave device that has an excellent temperature coefficient of frequency (TCF) and high accuracy of IDT pattern forming and is capable of resisting high temperature processing of 200 degrees or more. The method for manufacturing an acoustic wave device according to the present invention includes forming an IDT (2) on a principal surface (1a) of a piezoelectric substrate (1), and forming a film by thermal spraying a material (3) having a smaller linear thermal expansion coefficient than the piezoelectric substrate onto an opposite principal surface (1b) of the piezoelectric substrate (1) where the IDT (2) is formed.

This invention discloses a method for compensating crystal frequency temperature property based on temperature sensing material stress, which contains using vacuum plating method to plate temperature sensing double-metal material on the crystal chip or electrode of crystal resonator which can compensate the frequency variation due to temperature of crystal. Said method can make the frequency temperature property of crystal reach positive and negative 0.2ppm and simply the current circuit of temperature compensation with small volume and low cost.

The invention discloses a temperature compensation circuit for a laser drive, comprising a positive temperature coefficient current generation module, a zero temperature coefficient current generation module and a temperature compensation proportion control module, wherein the output ends of the positive temperature coefficient current generation module and the zero temperature coefficient current generation module are respectively connected with the input end of the temperature compensation proportion control module; the positive temperature coefficient current generation module can be used for generating positive temperature coefficient current increasing with the temperature rise so as to determine a slope factor for temperature compensation; the zero temperature coefficient current generation module can be used for generating zero temperature coefficient current irrelevant with the temperature so as to determine the initial temperature of the temperature compensation; and the temperature compensation proportion control module can be used for sampling the difference between the positive temperature coefficient current and the zero temperature coefficient current and overlapping the difference with the external input current for controlling compensation current to determine the compensation current and further control the proportion of the temperature compensation, The temperature compensation circuit can be used for flexibly adjusting the compensation proportion of a laser and stabilizing the extinction ratio, adapts to the temperature characteristics of different lasers, and has strong generality.

The invention discloses a wireless passive temperature sensing system for a main transformer cabinet of an electric locomotive. The wireless passive temperature sensing system comprises a surface acoustic wave temperature sensing unit, an antenna unit and an acquisition unit, the surface acoustic wave temperature sensing unit is mounted at a to-be-measured temperature in a main transformer cabinetof the electric locomotive, and is connected with the acquisition unit through the antenna unit; and the surface acoustic wave temperature sensing unit comprises a substrate, a piezoelectric substrate, an antenna module, an interdigital transducer and a reflecting grating. The piezoelectric substrate comprises a sound wave conduction substrate and a piezoelectric film positioned on the sound waveconduction substrate; the sound wave conduction substrate is located on the substrate, and the antenna module, the interdigital transducer and the reflecting grating are located on the piezoelectricfilm; and a sound absorption layer is laid on the surface of the piezoelectric film and used for absorbing bulk acoustic wave signals in the acoustic surface waves. The system has the advantages of high frequency, low time delay, high sound velocity, high reliability, high adaptability and the like.

The invention provides a temperature compensation method, a temperature compensation auxiliary circuit and a voltage-controlled oscillation device, so as to improve the performance of a voltage-controlled oscillator. The temperature compensation auxiliary circuit comprises a conversion module and a voltage selection module, wherein an input end of the conversion module is used for inputting temperature information, and the conversion module is used for converting the temperature information into a control signal and outputting the control signal; and the voltage selection module is coupled tothe conversion module, selects a voltage under the action of the control signal output by the conversion module, and outputs the selected voltage.

A method for forming a surface acoustic wave resonance device relates to the technical field of semiconductors, and comprises the following steps: providing a piezoelectric substrate which comprises a first spacer region, a first region, a second region, a third region and a second spacer region which are sequentially arranged along a first direction; forming an electrode layer on the surface of the piezoelectric substrate, wherein the electrode layer comprises a first bus, a second bus, a plurality of first electrode strips connected with the first bus, and a plurality of second electrode strips connected with the second bus; a first temperature compensation layer is formed on the surfaces of the piezoelectric substrate and the electrode layer, the first temperature compensation layer comprises a first compensation area and a second compensation area, and the surface, on the first compensation area, of the first temperature compensation layer is higher than the surface, on the second compensation area, of the first temperature compensation layer; and forming a first load layer located on the first region and a second load layer located on the third region on the surface of the first temperature compensation layer. Therefore, an existing forming process is improved.

The invention discloses an all-fiber sensing belt conveyor weighing device and a weighing method thereof. The weighing device comprises a belt conveyor belt (1), a weighing frame (2), a belt conveyor rolling wheel (3), a fiber weighing sensor, a speed fiber sensor, a fiber splicing box (8) and a control room (16). The belt conveyor rolling wheel (3) is arranged on the weighing frame (2). The belt conveyor belt (1) is arranged on the belt conveyor rolling wheel (3). The fiber weighing sensor is arranged on the weighing frame (2). The speed fiber sensor is connected with the belt conveyor rolling wheel (3). The fiber weighing sensor and the speed fiber sensor are respectively connected with the fiber splicing box (8) via fibers. The fiber splicing box (8) and the control room (16) are connected via the fibers. The control room (16) processes the received signals and displays weighing weight and belt speed. The weighing device is suitable for more accurate weighing of bulk materials in dusty, moist and corrosive operation occasions and/or flammable and explosive operation occasions.

The invention relates to a temperature compensation method for a wireless sensor network dip fulcrum. The temperature compensation method comprises the following steps that (1) angel values and temperature values of a to-be-detected structure object within the monitoring cycle are collected through the wireless sensor network dip fulcrum; (2) the structure stability period, namely the time periodduring which a structure does not generate inclination and deformation, is determined according to the angel values within the monitoring cycle; (3) a temperature compensation model of the wireless sensor network dip fulcrum is established, and a temperature compensation coefficient is calculated; and (4) according to the temperature compensation model after obtaining the temperature compensationcoefficient, the collected angle values of the wireless sensor network dip fulcrum are automatically compensated. Compared with the prior art, the temperature compensation method has the advantages that temperature testing is not needed, automatic compensation is conducted, the compensation efficiency is improved, and a field application environment is fit.

The invention relates to a valve, and in particular relates to a pilot type active belt position monitoring safety valve. The pilot type active belt position monitoring safety valve comprises an electromagnetic directional valve (21), a main valve (20) and a check valve, wherein the main valve (20) comprises a valve sleeve (2) with a stepped hollow inner part, an outlet A is formed in the right end of the valve sleeve (2), a port B communicated with an oil inlet is formed in the circumference of the right end of the valve sleeve (2), and a lantern ring (4) is installed in the left end of the valve sleeve (2); a valve core (3) with a boss in the middle is installed in the valve sleeve (2), linear sealing is formed between the outer conical surface of the right end of the valve core (3) and an inner conical hole in the right end of the valve sleeve (2) to separate a port A from the port B, the right end of the valve core (3) extends into the lantern ring (4) in a matching way, the boss in the middle of the valve core (3) is matched with the inner wall of a large hole in the left end of the valve sleeve (2), and the cylindrical surface on the right side of the boss of the valve core (3) is matched with the inner hole in the middle of the valve sleeve (2) is a sealing way. The pilot type active belt position monitoring safety valve is reasonable to design and simple in structure.

An anesthetic vaporizer and a temperature compensation unit are disclosed. The temperature compensation unit, which cooperates with a vaporizing chamber having a bottom wall, includes a first device connected to the bottom wall of the vaporizing chamber for contacting with liquid anesthetic agent in the vaporizing chamber and changing in length according to temperature change of the liquid anesthetic agent, and a second device connected to the vaporizing chamber. A gas flow gap through which a gas flow passes is formed between the first and second devices. The gas flow gap becomes larger as temperature of the liquid anesthetic agent rises and smaller as the temperature of the liquid anesthetic agent drops. Since the first device is connected with the bottom wall of the vaporizing chamber, the first device will directly contact with the liquid anesthetic agent regardless of the liquid level of the anesthetic agent, as long as there is liquid agent in the vaporizing chamber; therefore the efficiency of heat exchange is high and the effect of temperature compensation is good.

The invention discloses a wireless passive temperature compensation method for a film bulk acoustic wave pressure sensor. On the one hand, the film bulk acoustic wave sensor of a conventional transmitter is replaced with a pair of parallel sealed and unsealed film bulk acoustic wave devices. On the other hand, a conventional wired active temperature compensation method is replaced with a wirelesspassive temperature compensation method. Compared with traditional piezoresistive pressure sensors and capacitive pressure sensors, the film bulk acoustic wave pressure sensor has high sensitivity andhigh resolution, presents the same in the form of frequency, and is less affected by electromagnetic interference.