42results about How to "Solve the difficulty of selection" patented technology

The invention provides a double-wall pipe ventilation system for an LNG power ship. The double-wall pipe ventilation system for the LNG power ship comprises a first ventilation air inlet pipeline, a flow meter, a first double-wall pipe, a second double-wall pipe, fuel gas equipment, a fuel gas inlet pipeline, a GVU valve set, a pneumatic adjustment valve, a second ventilation air inlet pipeline, afirst exhaust fan and a ventilation air outlet pipeline. According to the double-wall pipe ventilation system for the LNG power ship, the double-wall pipes are arranged in a cabin to supply gas to the fuel gas equipment, and the risk that the gas leaks into the cabin is reduced through the good protection function of the double-wall pipes. The exhaust fan is arranged to conduct mechanical exhauston the annular space in the double-wall pipes, the negative pressure state of the annular space is maintained, and it is guaranteed that once gas leaks, the gas can be exhausted out of the ship at the highest speed.

A power supplying system for a magnetic bearing and a control method thereof are disclosed. The system includes a rectifier filter circuit (1), a power acquiring circuit (9) and a DC-DC power supply (2), wherein the rectifier filter circuit (1) performs rectification and filtration treatment on an alternating current input power source to obtain a first direct-current busbar voltage; then the first direct-current busbar voltage is divided into two parts; one part supplies power to a motor controller (5) of a motor (6) of the magnetic bearing; the power acquiring circuit (9) acquires power fromthe other part of the first direct-current busbar voltage to obtain a second direct-current busbar voltage; the second direct-current busbar voltage is in an allowable input voltage range of the DC-DC power supply (2); and the DC-DC power supply (2) converts the second direct-current busbar voltage into a third direct-current busbar voltage and supplies power to a bearing controller (4) of the magnetic bearing (3). The system and the method can overcome poor power supply stability, a complex structure, poor reliability, and other defects in the prior art, and achieve good power supply stability, a simple structure and good reliability.

The invention relates to a method for inhibiting an induction voltage and an induction current of a 750kV parallel single-line construction line. Two large-distance parallel and single-line construction 750kV alternating current transmission lines are coupled on an off-the-line line to generate a higher induction voltage and a higher induction current to ensure that the problem of difficult equipment selection caused by exceeding the turning on or off capacity of the existing 750kV earthing switch is solved. The invention provides a transposition and phase sequence arrangement mode to ensure that levels of the induction voltage and the induction current applying the measure are remarkably reduced and are lower than the requirement on technical parameters of the existing equipment, and thus the equipment selection problem is solved.

The invention discloses a high temperature lepidolite hydrothermal treatment method for producing lithium hydroxide. The method comprises following steps: step one, carrying out mechanical activation;step two, preparing raw materials; step three, carrying out preheating reactions; step four, performing hydrothermal reaction; step five, carrying out leaching and concentration; step six, removing salt: cooling concentrate at a temperature of 20 to 30 DEG C, and stirring the concentrate for 60 to 90 minutes to carry out crystallization to obtain a coarse product of lithium hydroxide. The methodhas the advantages of low energy consumption, cleanness, environmental friendliness, low cost, and high leaching efficiency, and is a novel method for fixing fluorine of lepidolite and leaching valuable metals. High temperature hydrothermal reactions are adopted to improve the burning performance of materials, and the problems that lepidolite is hard to melt at a high temperature and HF gas is generated during the melting process are solved. Moreover, the lithium conversion rate is largely improved at a proper temperature during a proper period, the technology is simpler, the material flux issmall during the production process, the recovery rate of lithium and alkali metals is high, and valuable metals are fully utilized.

The invention discloses a pipeline system, a venturi fertilizer applicator type selecting method, and applications thereof, and belongs to the field of water fertilizer integration. The venturi fertilizer applicator type selecting method comprises following steps: based on on-site factors, an irrigation device matching the on-site factors is selected, wherein the irrigation device comprises certain characteristic parameters, the on-site factors comprises one or a plurality of factors selected from crop, soil type, and irritation rules; based on the characteristic parameters, the working flowamount of the pipeline system and the outlet flow amount of a venturi fertilizer applicator contained by the pipeline system are determined, so that the venturi fertilizer applicator is determined based on the working flow amount of the pipeline system and the outlet flow amount of the venturi fertilizer applicator. The venturi fertilizer applicator type selecting method is capable of solving problems in the prior art that venturi fertilizer applicator type selecting is difficult, and fertilizer absorption is difficult to realize, time and cost are saved greatly, and it is beneficial for waterfertilizer integration high efficiency utilization.

The invention provides a power unit bypass protection device. A common mechanical switch is used to replace a mechanical-type rapid switch with a specific model. Thyristors V1 and V2 are arranged, and a first voltage division circuit and a second voltage division circuit are arranged too. When a power unit has a fault, through driving a thyristor V3 in the first voltage division circuit to be conducted, the thyristor V1 is controlled to be conducted, or through driving a thyristor V4 in the second voltage division circuit to be conducted, the thyristor V2 is controlled to be conducted. Before a switch K2 is closed, the thyristor V1 or the V2 achieves an effect of carrying out short circuit on the fault power unit so as to remove the fault power unit from a flexible direct current power transmission system. After the switch is closed, the switch bypasses the fault power unit. Because response time of the thyristor is less than response time of the common mechanical switch, through using the thyristor, failure response time can be shortened to a nanosecond level so that problems that component type selecting is difficult and cost is high are solved.

The invention discloses an optimal scheme selecting method based on a distributed photovoltaic access design cluster model. The optimal scheme selecting method includes steps of defining a set of N design schemes; determining state variables indicating distributed photovoltaic design characteristics; defining state vector by the state variables indicating distributed photovoltaic design characteristics; setting up the cluster model based on information entropy, projecting the integral characteristic parameter set in design scheme space, and classifying all characteristic vectors into N types by a high-dimensional categorical data subspace cluster algorithm based on information entropy; calculating distance between characteristic vectors of a newly built photovoltaic access design model and those of the current cluster model based on the current cluster model for those newly built grid-connected photovoltaic, and selecting a category where the characteristic parameters with the smallest distance are, that is, the corresponding optimal design scheme. On one hand, an existing model database can be enriched; on the other hand, designers can be quickly instructed to select the optimal scheme.

The invention discloses a method for designing a fish finder transmitter signal source, and specifically relates to a method for designing a fish finder transmitter sine wave signal source suitable for a D-class power amplifier. The method for designing the fish finder transmitter signal source adopts a Delta-Sigma modulation technology, the generated signal source only needs to connect with a D-class digital power amplifier for amplification, and after high-frequency noise is filtered through a simple low pass filter, the signal source can restore and output sine wave signals, thereby providing for a fish finder transmitter a sin wave signal source which is capable of modulating amplitude and frequency through software and is suitable for a D-class power amplifier. The requirement for bandwidth of a power amplifier tube is substantially lowered, the problem of difficult model selection of the power amplifier tube is solved, the problem that a PWM mode causes output waveform distortion due to power amplifier tube pulse loss is avoided, and the output accuracy of the signal source is substantially improved; the design of the filter is greatly simplified; and amplitude modulation and voltage regulation output of the signal source can be realized without adding of an D/A chip.

The invention relates to the field of pipelines used for conveying of water, oil and the like, and discloses a pipeline. The pipeline comprises a metal cylinder (2) and a concrete cylinder (6) arranged outside the metal cylinder (2) in a sleeving manner. An elastic cushion layer (3) is arranged between the metal cylinder (2) and the concrete cylinder (6). The pipeline can bear high inner pressureand high outer pressure, good permeability resistance and durability are achieved, and the cost is low.

The invention relates to a hyperspectral image denoising method based on multi-target low-rank sparsity and space spectrum total variation. In combination with a multi-objective optimization theory, ahyperspectral image denoising recovery problem is converted into a multi-objective optimization problem of a sparse noise image item, a low-rank clean image item and a data fidelity item in combination with a spatial-spectral total variation item. The sparse noise is modeled by using the 10 norm, and the low-rank term is modeled by using the nuclear norm. Then, the three target items are optimized at the same time through the strong optimizing capacity of the multi-target evolutionary algorithm, and the model is solved to achieve the optimal set of solutions. According to the method, the problems of inaccurate l1 norm sparsity modeling and difficulty in optimal regularization parameter selection in an existing hyperspectral image sparse denoising method can be solved, and in addition, a sub-fitness updating strategy is designed, so that the algorithm is carried out more effectively. According to the invention, the applicability and precision of hyperspectral image denoising can be effectively improved.

The invention provides a light source structure of an automotive LED headlamp. The light source structure comprises an LED light source I, an LED light source II, a light-reflecting bowl, an optical lens and a light barrier, wherein the light-reflecting bowl is provided with at least two or more optical centers, the LED light source I is arranged at one optical center of the light-reflecting bowl, the LED light source II is arranged at the other optical center of the light-reflecting bowl, the LED light source I and the LED light source II are staggered at an interval of the distance conforming to the size of the LED light sources, the optical lens is arranged at the position of a light outlet of the light-reflecting bowl, and the light barrier and the optical lens are linearly distributed with the optical lens as the axis. The two light sources producing luminous energy are combined, and then the unique optical lens is utilized to form an automotive optical lens assembly completely conforming to the illumination laws and regulations of the automotive headlamp, so that the few-type requirement for a single LED light source of light-distribution laws and regulations of the automotive headlamp is met, and the problem of difficult type selection is solved.

The invention discloses a selecting method for an optimal initial row of an optical touch image. The functional modules comprise an optical sensor signal processing unit, an image signal interface unit, an image optimal initial row automatic adjusting unit and an optical sensor calibrating unit. The selecting method for the optimal initial row comprises the following steps of: acquiring, processing and transferring an image signal displayed on a touch screen; automatically selecting the optimal initial row of the image according to the image signal; and automatically selecting the optimal initial row of the image according to the image signal. The self-adaptive adjusting method is adopted for solving the problem that the initial row of the image is difficult to select under a complex environment. The robustness of the selecting method is remarkably improved, so that the calibration of the optical sensor is more stable; the instantaneity is strong; the extracting precision is high; and the operation is easy. When the touch screen is installed, the factors such as illumination and the like of the installation environment of the touch screen are not needed to be evaluated; and the installation environment of the touch screen is unnecessary to take into consideration. In particular under the industrial mass-production mode, the selecting method provided by the invention is easier to realize and has high mass-production efficiency.

The invention relates to a modularization multi-level current converter bridge arm current direction measuring device and a judgment method. The modularization multi-level current converter bridge arm current direction measuring device comprises a first single chip microcomputer U1, a second single chip microcomputer U2, a first current sensor TA1, a second current sensor TA2, a first operational amplifier U3, a second operational amplifier U4, a first photoelectric coupler U5, a second photoelectric coupler U6, resistors R1-R16, a capacitor C1 and a capacitor C2. The modularization multi-level current converter bridge arm current direction measuring device has the advantages that the bridge arm current direction is indirectly judged by detecting the current situation of an internal switching tube of a submodule according to the switching tube conduction state, and the requirement for the insulating degree of the current sensors can be greatly reduced; meanwhile, power supplies of the sensors can be isolating power supplies of a submodule drive protection circuit, and a circuit does not need to be additionally arranged; the complex degree and cost of the modularization multi-level current converter bridge arm current direction measuring device can be greatly reduced according to the characteristics, and reliability can be improved.

The invention discloses a wheel edge speed reducing device and a brake system thereof, and relates to the technical field of wheel edge speed reduction. The wheel edge speed reducing device comprises a first-grade straight tooth transmission mechanism, a first-grade planet speed reducing mechanism and a second-grade planet speed reducing mechanism; a power input end of the first-grade straight tooth transmission mechanism adopts multiple driving gears; hydraulic motors can supply power to the driving gears; a power output end of the first-grade straight tooth transmission mechanism adopts a driven gear; the driven gear is connected with the first-grade planet speed reducing mechanism, and transfers the power to the first-grade planet speed reducing mechanism; and the first-grade planet speed reducing mechanism is connected with the second-grade planet speed reducing mechanism, and transfers the power to the second-grade planet speed reducing mechanism. The wheel edge speed reducing device uses multiple hydraulic motors to supply the power for common driving; and multiple small hydraulic motors are adopted to replace a large hydraulic motor to drive the wheel edge speed reducing device to operate, so that the problem of difficult model selection of high-horsepower all-hydraulic bulldozer motors is solved, and meanwhile, the production cost can be largely reduced. The invention further proposes a brake system of the wheel edge speed reducing device.

The invention provides a series diode circuit. The series diode circuit comprises a first PCB and a plurality of diodes, the plurality of diodes are arranged on the first PCB, and the plurality of diodes are sequentially connected in series through a plurality of first wires laid on the first PCB; the series diode circuit further comprises a plurality of second wires which are laid on different layers from the first wires, and the second wires are used for generating parasitic capacitance so as to carry out voltage-sharing compensation on the series diode circuit. According to the invention, the problem that the compensation capacitor of the series diode circuit is difficult to select in the prior art is solved, and the selection difficulty of the compensation capacitor of the series diodecircuit is reduced.