121results about How to "Small fluctuation" patented technology

The application discloses a hydraulic system for stabilizing pressure of a hot-pressing sintering aluminum nitride heater, which comprises a main oil tank and a stamping oil cylinder; the main oil tank is connected with a first main oil path, the first main oil path is connected with an upper cylinder total oil path and a lower cylinder oil path through a first two-position cartridge valve, the upper cylinder total oil path is connected with an inner cylinder oil path and the main oil tank through a second two-position cartridge valve, and an outer cylinder oil path is connected with the inner cylinder oil path through a cartridge valve; the first main oil path, a second main oil path and a third main oil path are connected with a pressure compensation main oil path; a first hydraulic control check valve is arranged on the inner cylinder oil path and the outer cylinder oil path, the first hydraulic control check valve is connected with a first pressure relief oil path connected with the second main oil path, and the inner cylinder oil path and the outer cylinder oil path are connected with a second pressure relief oil path between the first hydraulic control check valve and the stamping oil cylinder. The design of the inner cylinder and the outer cylinder can realize controllable pressure relief range of the stamping oil cylinder, the pressure relief oil path makes the stability of the pressurizing rate good, and the pressure fluctuation is small during the pressure relief process.

A kind of plane connecting rod end effector switching control method and system based on deviation and load state belong to motion adjustment control technical field.The method includes: obtaining target trajectory, current control mode, current target load level and safety threshold;Real-time acquisition of end execution point actual position, actual speed, drive joint state and drive load information;According to trajectory deviation, load state and abnormal duration determine current control state;In recoverable deviation state, execute first-level regulation, in protection control state, execute second-level regulation;When continuously meet recovery condition, restore autonomous tracking control mode, or execute autonomous tracking control mode with recovery target load level.The present application can improve trajectory stability, regulation continuity and operation safety margin of end effector in man-machine collaborative motion.

The invention discloses a quenched and tempered seamless line pipe with narrow strength fluctuation and a manufacturing method thereof. The quenched and tempered seamless line pipe comprises the following components in percentage by weight: 0.06-0.10% of C, 1.40-1.65% of Mn, less than or equal to 0.05% of Cu, less than or equal to 0.05% of Ni, less than or equal to 0.05% of Cr, less than or equal to 0.30% of Si, 0.05-0.20% of Mo, 0.01-0.05% of Nb, 0.03-0.07% of V, less than or equal to 0.020% of Ti, less than or equal to 0.0005% of B, less than or equal to 0.015% of P, less than or equal to 0.005% of S and the balance of Fe or other impurity elements. And Cu + Ni + Cr is less than or equal to 0.10%. According to the method, the strength fluctuation of the whole seamless pipeline pipe product after thermal refining is smaller than 25 MPa, the strength performance stability can be improved, and the use performance of the product is improved.

The application relates to the technical field of water purification equipment, and provides a water outlet pipe structure of a water purifier, which comprises a water outlet pipe body, the water outlet pipe body comprises a first pipe body and a second pipe body which are communicated with each other and perpendicular to each other, water flows through the first pipe body and flows out along the pipe opening of the second pipe body, a rib is connected in the second pipe body, the central axis of the rib is in the same line with the central axis of the first pipe body, the rib extends to one side of the outlet of the second pipe body, and a spacing is left between the rib and the side wall of the second pipe body which is close to one side of the first pipe body. Based on the above, the water outlet pipe of the water purifier is leveled, and the economic burden is reduced.

The application relates to the technical field of building materials, and discloses an L-shaped ALC corner wallboard, which comprises a corner reference plate and a corner adjusting plate, the corner adjusting plate is arranged on one side of the corner reference plate, one side of the corner reference plate is provided with a circular arc surface, the corner adjusting plate is provided with an arc-shaped groove, the inner wall of the arc-shaped groove is in contact with and matched with the circular arc surface, the installation and connection of the corner reference plate and the corner adjusting plate are completed in the mode that circular clamping blocks and connecting pieces are clamped, the strip-shaped pressing plate is driven to move by rotating the lower pressing disc, the position of the pressing plate is adjusted, the pressing plate is away from the corresponding circular clamping block, the corresponding two circular clamping blocks are away from the connecting spherical body, the connecting spherical body can be taken off from the circular clamping block, and the corner reference plate and the corner adjusting plate can be disassembled and replaced.

This utility model discloses a receiver-type automotive fuel level sensor, including an electrical box, a signal output line, and a flange. A probe rod is installed at the bottom of the electrical box, and the flange is installed on the outside of the probe rod. A monitoring and control mechanism is provided inside the probe rod, and a gauging groove is provided inside the probe rod. A float is slidably connected to the inner wall of the gauging groove. The probe rod has an oil inlet and an exhaust port. The gauging groove is connected to the external space through the oil inlet and the exhaust port. The monitoring and control mechanism includes a combined sensor, a PLC control unit, and a telescopic rod. By dynamically adjusting the opening of the exhaust port through the telescopic rod, large fluctuations in the fuel level in the gauging groove are suppressed, and the pressure in the internal space of the gauging groove above the float is increased, making the float more stable, reducing the frequency and amplitude of shaking, and reducing the displacement signal fluctuation caused by the inertia of the float, so that the fuel level signal transmitted to the instrument is more stable.

The embodiment of the invention provides a control method of a refrigerator, a controller, the refrigerator and a storage medium, the control method of the refrigerator is applied to the refrigerator, and the refrigerator is in communication connection with a server; the method comprises the following steps: acquiring food material information of put food materials, and sending the food material information to a server; and receiving a target working strategy of the compressor fed back by the server based on the food material information, and controlling the compressor according to the target working strategy. Due to the fact that the refrigerator is in communication connection with the server, the refrigerator can control the compressor according to the target working strategy, fed back by the server based on the food material information, of the compressor, and the temperature in the refrigerator is kept in a relatively stable state all the time; and the loss of the existing food materials in the refrigerator caused by dramatic temperature change is avoided, so that the temperature fluctuation is reduced, and the fresh-keeping effect is improved.

The application provides a continuous production method and system of calcium hydroxide with high whiteness and high specific surface area, and relates to the technical field of limestone deep processing. The continuous production method comprises the following steps: step one: continuously adding quicklime particles into the inlet of a primary digester, continuously adding digestion water and an additive into the inlet of the primary digester, and carrying out premixing and pre-digestion under stirring conditions; step two: continuously introducing the discharge of the primary digester into a secondary digester, continuously adding digestion water and an additive into the inlet of the secondary digester, and stirring and digesting and aging; step three: the discharge of the secondary digester is sequentially introduced into a tertiary digester, a quaternary digester and a quinary digester for digestion and aging, and the product is obtained after grading by a grader. The method can continuously prepare calcium hydroxide with high whiteness and high specific surface area, and has the characteristics of simple process, short time consumption, remarkable effect and low energy consumption, and has been applied in actual production and has good use effect.

The invention relates to the field of infrared touch screen control, in particular to a control method and system of an infrared touch screen. The method comprises the following steps: acquiring a transmitting unit set, a receiving unit set and a forbidden list, performing topology registration and signature codebook library assembly processing, and generating a scanning configuration packet; on the basis of the scanning configuration packet, executing transmission lightening time slot sequence generation, receiving time slot sampling and dark time slot baseline deduction matching decoding processing, and generating a decoding evidence packet; based on the decoding evidence packet, baseline offset calculation is carried out, spatial form evidence and time consistency evidence generation processing is carried out, a gating evidence packet is constructed, evidence gating and anomaly classification processing is carried out, and a control output packet is generated; and extracting a verification rescanning strategy parameter from the control output packet, executing verification rescanning and passing mark generation processing, generating a rescanning result packet, and constructing a write-back update packet. According to the invention, through an evidence link and a re-scanning write-back closed loop organization, the caliber consistency and traceability of control output are improved.

The invention discloses a method and a device for improving the concentration of sludge fed into a dehydrator, relates to the field of sewage treatment, utilizes the existing sludge return pipeline as a residual sludge taking point, does not need to add an additional sludge concentration facility, simplifies the process flow, and saves the land occupation and capital construction investment. Meanwhile, the sludge concentration control and the sludge inlet requirement of a dewatering system are unified, the sludge return ratio is accurately regulated and controlled, the return sludge concentration is stabilized in a proper range required by efficient operation of the dewatering machine, the sludge inlet concentration is improved and stabilized, the dewatering performance of the sludge is improved, and a dual regulation strategy of coarse regulation of the number of machines and fine regulation of the frequency is adopted; the large-amplitude change can be quickly responded, fluctuation can be reduced, fine adjustment can be carried out in a steady state, frequent starting and stopping of the pump and severe fluctuation of reflux quantity are avoided, and impact on equipment is small.

The application discloses a cyclone combustion system of a wing wall furnace boiler, wherein the lower furnace, the main combustion area furnace and the upper furnace all comprise a front wall, a right side wall, a back wall and a left side wall; the front wall, the right side wall, the back wall and the left side wall of the main combustion area furnace are all provided with inclined wing walls between two adjacent sides; each of the four wing walls is provided with a wind distribution chamber; each of the four wind distribution chambers is provided with a burnout air device and two or more layers of cyclone pulverized coal burners from top to bottom; the axes of the burner nozzles of the cyclone pulverized coal burners of the same layer in the four wind distribution chambers are arranged in a diagonal line in pairs; and the cyclone pulverized coal burners of the same layer in the four wind distribution chambers are all connected with the same coal mill; the application can improve the self-stable combustion capacity, the uniformity of the airflow in the furnace and the flame fullness, avoid the flame brushing the wall, realize the good combustion air power flow field organization in the furnace, precisely control the smoke temperature deviation, ensure the safe operation of the large-capacity high-parameter boiler and better meet the high-index requirement of the new generation of coal power technology.

This invention relates to the field of electronic digital data processing technology, specifically a communication resource allocation method for multi-agent systems. The method acquires the actions output by agents and the global system throughput in each resource allocation cycle. By constructing a counterfactual baseline network, and under the condition that the actions of other agents are fixed and the current agent's action is replaced, the marginal contribution value of the current agent to the global system throughput is calculated as the individual credit reward. To address the total transmit power limit and minimum signal-to-interference-plus-noise ratio (SNR) requirement of the communication network, these are transformed into penalty terms using the Lagrange duality method. A final loss function is constructed based on the individual credit reward minus the penalty term, and this loss function is used to calculate the gradient update policy network parameters. This invention eliminates the interference of other agent actions on the reward, decouples physical constraints from the reward, and makes the updated policy parameters constrained by the power boundary and SNR threshold of the communication system.

The present application relates to the technical field of catalyst production, in particular to a preparation method of methanol synthesis catalyst with stable precipitation process, comprising the following steps: step 1: dissolving zirconium nitrate, zinc nitrate and aluminum nitrate in water to form a zirconium-zinc-aluminum mixed salt solution A, dissolving zinc nitrate, aluminum nitrate and copper nitrate in water to form a copper-zinc-aluminum mixed salt solution B, dissolving sodium carbonate in water to form alkali solution C and alkali solution D, and adding a small amount of alkali solution C into deionized water to form deionized water E; step 2: using the salt solution A, the alkali solution C and the deionized water E to form a precipitate 1, and then aging the precipitate 1; step 3: after aging, filtering and washing the precipitate 1, adding the precipitate 1 into the mixed solution B to form a highly dispersed suspension slurry F; step 4: using the suspension slurry F and the alkali solution D to perform an emulsification reaction to form a precipitate 2, and aging the precipitate 2.

The invention belongs to the technical field of spinning, and relates to a drafting device for improving the dry uniformity of vortex spinning lines. The vortex spinning front drafting area comprises a front roller, a front pressing roller, a middle roller, a middle pressing roller, an upper pin, two symmetrical upper rubber rings, a lower pin, two symmetrical lower rubber rings, a small pressing roller, a transmission assembly and a lifting mechanism. The small compression roller is parallel to the middle compression roller, penetrates through the two upper rubber rings at the same time and makes contact with the upper surfaces of the working edges of the two upper rubber rings, the distance between the contact point and the jaw of the front roller is D1, the length of the spun fiber raw material is L, and the absolute value of the difference value between D1 and L does not exceed 3 mm; the transmission assembly is used for driving the small compression roller to operate along with the middle roller in the same direction and at the same speed so as to apply acting force F1 parallel to the operation advancing direction of the working edges of the upper rubber rings to the two upper rubber rings; and the lifting mechanism is used for adjusting the height of the small compression roller so as to apply a vertically downward acting force FN to the two upper rubber rings. The drafting device is simple in structure, and the air vortex spinning line evenness can be effectively improved.

The invention provides a high-voltage ride-through control method and device of a grid-connected converter, a controller and the grid-connected converter. The method comprises the following steps: monitoring a power grid voltage of a common coupling point of a power grid and a grid-connected converter in real time, and judging whether the grid-connected converter enters a high voltage ride through state or not according to the power grid voltage; if the grid-connected converter enters the high-voltage ride-through state, reducing a reactive current regulation coefficient within a first preset duration of entering the high-voltage ride-through state; determining a reactive current given value based on the power grid voltage and the reactive current adjustment coefficient; the reactive current adjusting coefficient is in positive correlation with the absolute value of the reactive current given value; and controlling the grid-connected converter by adopting the reactive current given value. According to the method, sudden change of the reactive current given value can be restrained from the source, the reactive current overshoot phenomenon is avoided, and therefore the jitter problem that when the power grid voltage enters the high-voltage ride-through state, uprush is conducted firstly, and then falling back is conducted is effectively relieved.

The present application relates to the technical field of petroleum chemical industry, in particular to an automatic execution system and method for the material returning process of an ethylene cracking furnace, which comprises a state confirmation module before material returning, used for confirming initial parameters before material returning, and when the initial parameters are within an initial range, indicating that material returning can be performed, and when the initial parameters are not within the initial range, giving an alarm; a material returning process control module, used for controlling key parameters of material returning in the material returning stage, and issuing a material returning instruction, wherein the key parameters of material returning include the material returning rate of a single pipe of a furnace chamber and the material returning rate of a total pipe of the furnace chamber; and a material returning module, used for receiving the material returning instruction and performing material returning. By using the system, the state before material returning is confirmed by the state confirmation module before material returning, and the key parameters of material returning in the material returning process are controlled by the material returning process control module, which can effectively improve the accuracy of material returning, and has the advantages of high material returning efficiency, high safety and small fluctuation.

This utility model discloses a temperature and humidity control device for a constant temperature and humidity test chamber, including a test chamber body. A fixed frame is sleeved on the inner wall of the test chamber body. Several sets of baffles are rotatably connected to the inner wall of the fixed frame. A transmission component is sleeved on one end of each baffle. A connecting joint is sleeved on the inner bottom wall of the test chamber body. A branch pipe is connected through the top of the connecting joint. A diffusion component is connected through the top of the branch pipe. The transmission component includes a gear ring sleeved on one end of each baffle. This temperature and humidity control device for a constant temperature and humidity test chamber, through the setting of the transmission component and baffles, achieves the effect of adjusting the direction and position of hot air, effectively avoiding local temperature accumulation or dead zones. At the same time, based on the temperature detected by the temperature and humidity sensor, the data is fed back to the integrated controller. The integrated controller controls the exhaust fan speed and the baffle angle, enabling rapid response to changes in temperature and humidity setpoints, reducing system fluctuations, and improving dynamic balance efficiency.

The present application relates to the technical field of automobile wire harness terminals, in particular to a crimping terminal, which solves the problems of the existing technology that the corrosion inhibitor layer is easy to flow off and the structure of piercing cannot effectively accommodate the oxide layer debris when the copper-aluminum terminal is crimped, comprising a conductor crimping part and a corrosion inhibitor layer, the inner side of the conductor crimping part is formed with a crimping surface for crimping with the conductor of the wire, and the corrosion inhibitor layer covers at least the crimping surface of the conductor crimping part; the corrosion inhibitor layer comprises a carrier and nano-conductive particles dispersed in the carrier, and the carrier is a drying oil; before the conductor crimping part is crimped with the wire, the corrosion inhibitor layer is a liquid coating coated on the crimping surface, and after the conductor crimping part is crimped with the wire, the corrosion inhibitor layer is solidified into a solid film. The beneficial effect is that the drying oil is creatively selected as the carrier of the corrosion inhibitor layer, which is solidified into a tough solid film after being crimped with the aluminum wire. The problem that the liquid coating is easy to flow off under the vibration working condition in the existing technology is solved.

The invention relates to a base transmission device for a liquid phase epitaxy horizontal silicon carbide epitaxial furnace, which comprises a transmission assembly, the transmission assembly comprises a first connecting rod, a second connecting rod and a connecting piece, one end of the second connecting rod and one end of the first connecting rod are detachably connected through the connecting piece, and the connecting piece can drive the first connecting rod and the second connecting rod to realize multi-angle deflection; the rotating assembly comprises a first shaft, a first shaft sleeve, a second shaft, a second shaft sleeve, a shell, a positioning piece and a base, the axis of the first shaft and the axis of the second shaft are perpendicular and arranged at an interval, the positioning piece close to the transmission assembly abuts against the first shaft sleeve in the axial direction of the shell, the positioning piece is detachably connected with the shell, and the shell is provided with a cavity and a plane part; the first shaft, the first shaft sleeve, the second shaft, the second shaft sleeve and the positioning piece are all arranged in the cavity, the base is arranged on the upper side face of the plane part, the device solves the problem of unstable rotation of the base through cooperative work of the transmission assembly and the rotating assembly, and the uniformity and stability of epitaxial growth are remarkably improved.

The invention discloses a sectional type roasting temperature control method suitable for a synthetic resin binder material, and relates to the technical field of temperature control, furnace body data is collected based on a temperature control platform, a digital twinborn model is constructed, and a plurality of temperature control traction pools are configured corresponding to the digital twinborn model, the temperature control traction pool comprises a control line, a main pool and a temperature control factor in the main pool, the main pool is configured corresponding to the digital twin model, and the control line is configured corresponding to the furnace body temperature controller. Data needing temperature control can be rapidly and accurately analyzed through the temperature control traction pool, the temperature of the furnace body can be collected and analyzed in real time, the temperature needing to be maintained can be rapidly obtained, temperature control data does not need to be transmitted, only temperature control factors need to be started, and the temperature control traction pool can be used for rapidly controlling the temperature of the furnace body. The number and the positions of the connected temperature control factors are obtained through the mobile nodes, the power needing to be controlled is determined, the temperature can be continuously and linearly controlled, and the temperature control response efficiency can be greatly improved.

The application discloses a high-strength and high-toughness Al-Ca-In series aluminum alloy low-oxygen spherical powder for additive manufacturing and a preparation method thereof, relates to the technical field of additive manufacturing powder, and comprises the following components in percentage by mass: 1.5-3.0% of magnesium, 0.15-0.60% of manganese, 1.0-2.0% of calcium, 0.06-0.25% of indium, 0.08-0.18% of zirconium and 0-0.05% of titanium, and the balance of aluminum and impurities, wherein the total oxygen is not more than 0.10%; the powder surface has a nitrogen-containing diffusion barrier layer with a thickness of 2-8 nanometers and an ultrathin oxide layer with a thickness of 0.5-2.0 nanometers in sequence, and the surface enrichment and interface capture indexes are limited; and the powder is prepared by high-temperature dissolution of manganese and zirconium, low-temperature segmented calcium addition, nitrogen-containing gas atomization and low-temperature micro-oxidation. The powder inhibits the surface migration and oxidation loss of calcium and indium, improves the component stability in recycling and forming, reduces defects and performance dispersion, and is suitable for the high-strength and high-toughness manufacturing consistency of thin-wall lattice load-bearing parts.

The present application relates to the technical field of carbon fiber production, and discloses a carbon fiber oxidation furnace system and a waste gas recovery process thereof. The carbon fiber oxidation furnace system comprises: a pre-oxidation system for pre-oxidizing carbon fiber precursor; a first flue gas treatment system for incinerating flue gas discharged from the pre-oxidation system and purifying the flue gas; a second flue gas treatment system for removing nitrogen oxides in flue gas discharged from the first flue gas treatment system; a discharge treatment system for treating part of flue gas discharged from the second flue gas treatment system and discharging the flue gas into the atmosphere; and a flue gas recovery system for conveying another part of flue gas discharged from the second flue gas treatment system and mixed with supplemented fresh air to the pre-oxidation system. The carbon fiber oxidation furnace system and the waste gas recovery process thereof can directly recover the treated flue gas into the oxidation furnace, thereby reducing energy consumption and waste gas discharge.

The utility model discloses a paste fixing device and a breaking force detection device. The paste fixing device comprises a first end part fixing structure, a second end part fixing structure and a probe moving channel, the first end part fixing structure and the second end part fixing structure are arranged at an interval in a first direction, the first end part fixing structure is used for fixing one end of a to-be-detected paste body, and the second end part fixing structure is used for fixing the other end of the to-be-detected paste body, so that the to-be-detected paste body is erected between the first end part fixing structure and the second end part fixing structure; a probe moving channel extending in the second direction is arranged between the first end part fixing structure and the second end part fixing structure, and the two ends of the probe moving channel in the first direction are correspondingly communicated with the first end part fixing structure and the second end part fixing structure respectively; the first direction is perpendicular to the second direction. According to the paste fixing device, more stable breaking force data with smaller fluctuation can be obtained by changing the fixing mode of the paste.

The application provides an outer rotor motor, which comprises a rotor assembly, a rotor shell, a stator assembly and a bearing. The end of the rotor assembly is connected with the axial end of the rotor shell, so that the rotor assembly can rotate integrally with the rotor shell. The bearing is located at the inner periphery of the axial end of the rotor shell to support the rotor shell. The axial other end of the rotor shell extends to the radial outer periphery of at least part of the structure of the stator assembly. The rotor shell can be driven to rotate by the stator assembly, so as to drive the rotor assembly to rotate integrally. According to the application, the arrangement of one bearing can be effectively reduced. Compared with the conventional outer rotor motor structure which needs to be provided with two bearings, or the scheme of one long bearing, the cost of one small but high-priced bearing is effectively saved, so that the cost of the outer rotor motor is reduced, and the noise and vibration are also reduced.

The application discloses a double-embedding model hybrid training method, system, device and storage medium, which is applied to the technical field of recommendation systems and comprises the following steps: determining the routing parameters of each classification feature based on the historical access information of the classification features in a training data set; selecting a corresponding embedding table for the classification features input currently according to the routing parameters; wherein the embedding table comprises a first embedding table and a second embedding table; extracting the embedding vector corresponding to the classification features from the selected embedding table, and performing forward calculation and loss calculation of the model based on the embedding vector; and updating the parameters of the first embedding table, the second embedding table and a downstream model according to the result of the loss calculation. The application simulates the embedding hybrid use mode in reasoning in the training stage, enhances the collaborative ability of the two embedding tables, and improves the performance and robustness of the model in a real reasoning scene.

The invention relates to a lifting type circuit breaker transfer trolley capable of being rapidly disassembled and assembled and adjusted in multiple directions, and belongs to the technical field of circuit breaker transfer trolleys. A control system with a control terminal as a core is introduced on the basis of a basic structure of the transfer trolley, and the control terminal presets a target butt joint height, an allowable left-right height difference threshold value and an allowable dip angle threshold value; the state detection module detects the left-right height of a tray, the inclination angle of the tray and the braking in-place state, and the control terminal sends instructions to the lifting execution module and the interlocking prompt module according to detection signals and a preset threshold value. The lifting is allowed after the braking is in place, the lifting is stopped or prompted after the target height is reached, the leveling is prompted and the push-in or pull-out is limited when the posture exceeds the limit, and the problems that the butt joint height and posture of the tray of the circuit breaker transfer trolley are difficult to be stable and consistent and the braking state is lack of reliable constraint are solved. And interference, slippage and poor butt joint consistency are easy to occur in the push-in or pull-out process.

The application provides a structure for enhancing the coupling stability of a coaxial feed antenna array coupling calibration network, comprising a dielectric substrate, a coupling calibration network and an antenna, the coupling calibration network is arranged inside the dielectric substrate, a metalized via is formed on the dielectric substrate, the antenna is arranged in the metalized via, the metalized via is divided into left and right two circular arc surfaces, a rectangular slot structure is formed on the upper layer of the left circular arc surface, a semicircular ring slot structure is formed on the lower layer of the left circular arc surface, and the end of the coupling calibration network is conformal to the left circular arc surface. Compared with the metal rod / metalized via structure and the hair button structure, the coupling calibration network of the application has high stability, small fluctuation and small phase deviation.

The application belongs to the technical field of loudspeakers, and particularly relates to a double-magnetic-circuit high-flux-density magnetic circuit structure of a bone conduction loudspeaker. The technical scheme is as follows: a double-magnetic-circuit high-flux-density magnetic circuit structure of a bone conduction loudspeaker, comprising an upper outer ring magnet, an outer ring magnetic conducting member, a lower outer ring magnet, an upper inner ring magnet, an inner ring magnetic conducting member, a lower inner ring magnet and a voice coil; the upper outer ring magnet, the outer ring magnetic conducting member and the lower outer ring magnet form an outer ring magnetic circuit system, the upper inner ring magnet, the inner ring magnetic conducting member and the lower inner ring magnet form an inner ring magnetic circuit system, and the voice coil is arranged in an annular magnetic gap formed between the outer ring magnetic circuit system and the inner ring magnetic circuit system. The application provides the double-magnetic-circuit high-flux-density magnetic circuit structure of the bone conduction loudspeaker, which can guide to improve the magnetic flux density of the magnetic gap and improve the driving efficiency through a more reasonable magnetic circuit structure and magnetic conducting structure.

The application provides a sub-module quantity optimization configuration method of a modular multilevel converter, relates to the field of converters, and is applied to a segmented half-bridge-full-bridge hybrid modular multilevel converter including three-phase bridge arms, each phase bridge arm being composed of an upper bridge arm and a lower bridge arm, the upper bridge arm including cascaded half-bridge sections and full-bridge sections, the half-bridge section including at least two cascaded half-bridge type sub-modules, and the full-bridge section including at least two cascaded full-bridge type sub-modules, and the method comprises the following steps: constructing an amplitude function of an energy difference term of the half-bridge section and the full-bridge section; constructing an energy coupling degree function of the half-bridge section and the full-bridge section; constructing a bridge arm energy coordination function based on the amplitude function of the energy difference term of the half-bridge section and the full-bridge section and the energy coupling degree function; and determining the number of the half-bridge type sub-modules included in the half-bridge section and the number of the full-bridge type sub-modules included in the full-bridge section, so that the converter has the advantages of efficient and reliable support.

This invention belongs to the field of medical device technology, and particularly relates to a puncture device with integrated internal and external air conduction. Addressing the problem that existing puncture devices cannot prevent the outward escape of aerosols generated by chemotherapy drugs applied to the surgical site, this invention provides a puncture device with integrated internal and external air conduction, including a puncture device cannula assembly with an internal instrument channel, and a balloon assembly connected to the puncture device cannula assembly; it also includes an exhaust assembly disposed outside the puncture device cannula assembly, one end of which is connected to an external vacuum source, and the other end of which is connected to the instrument channel. A gas-conducting fixator is also provided outside the puncture device cannula assembly, with its bottom communicating with the patient's pneumoperitoneum, and the gas-conducting fixator is connected to the exhaust assembly. This invention achieves dual aerosol absorption through a dual negative pressure suction system, greatly reducing the risk of medical personnel inhaling toxic aerosols during minimally invasive surgery requiring chemotherapy.