Real-time prediction method for internal gap state of laser metal additive deposition

The invention belongs to the technical field of laser metal additive manufacturing, and particularly discloses a laser metal additive deposition internal gap state real-time prediction method, which comprises the following steps of: 1, acquiring multiple groups of single-channel multi-layer molten pool optical images under different process parameters, processing the optical images into optical image samples, and dividing the optical image samples into a training set and a test set; 2, establishing a deep learning porosity prediction model; 3, inputting the training set into a deep learning porosity prediction model for training; 4, inputting the test set into the trained deep learning porosity prediction model for verification to obtain a final deep learning porosity prediction model; and 5, inputting the real-time data into the final deep learning porosity prediction model to carry out real-time prediction on the internal pore state. According to the method, the optical molten pool image ...

Triangle wave signal generation method and triangle wave generator

The invention relates to a triangle wave signal generation method and a triangle wave generator. The generator comprises a triangle wave parameter processing unit and a triangle wave generating unit. The triangle wave parameter processing unit is used to process triangle wave parameters to obtain a frequency control word, a time threshold, and an amplitude coefficient. The triangle wave generating unit is used to generate a triangle wave signal according to information obtained by the triangle wave parameter processing unit. The triangle wave generating unit comprises: a phase accumulating module for accumulating the frequency control word once on a rising edge of a clock pulse TC of the triangle wave generating unit to generate a phase code; a comparison module for comparing the phase code and the time threshold obtained by the triangle wave parameter processing unit to generate a triangle wave mark; a selection module determining an output rising edge amplitude coefficient or a falling ...

Spectrum detection device based on MEMS movable micro platform and processing method thereof

The invention discloses a spectrum detection device based on an MEMS movable micro platform and a processing method of the spectrum detection device, and belongs to the technical field of spectrum analysis. The system comprises a metasurface, an MEMS movable micro-platform, a diaphragm, a single-point detector and a signal processing system. The metasurface, the MEMS movable micro-platform, the diaphragm and the single-point detector are all located on the optical axis of incident light. The metasurface is used for splitting and converging incident light, and the metasurface is composed of a microstructure with the feature size smaller than the working wave band of the spectrometer. The plane where the metasurface is located is perpendicular to the optical axis direction of incident light. The metasurface is used for focusing incident light and generating corresponding focuses at different positions in the optical axis direction according to different wavelengths. The metasurface is used ...

Imaging spectrometer based on MEMS movable micro-platform and array thereof

The invention discloses an imaging spectrometer based on an MEMS movable micro platform and an array thereof, and belongs to the technical field of spectral imaging. The system comprises a metasurface, an MEMS movable micro-platform array, a diaphragm and an image sensor. The metasurface is composed of a microstructure with the characteristic size smaller than the working wave band of the spectrometer. The metasurface is used as a dispersion element, so that the volume of the light splitting element is remarkably compressed; the metasurface is integrated on the MEMS movable micro-platform array, and the MEMS movable micro-platform array is processed by using a semiconductor process, so that the production cost of the imaging spectrometer can be reduced, and the integration level of the imaging spectrometer can be improved; the MEMS movable micro-platform array is used for dividing an object space into a plurality of areas for imaging, the spatial resolution with the maximum number the same ...

Burst-parameter-variable signal generator and cycle-number-variable signal generator

The invention discloses a burst-parameter-variable signal generator which comprises a clock unit, a control unit, an inner trigger unit and a waveform generation unit. The clock unit is used for generating a system clock. The control unit is used for receiving N different burst time intervals input from the outer portion, wherein N is larger than 1. The inner trigger unit is used for generating N inner trigger signals according to the N burst time intervals and the system clock. The waveform generation unit is used for generating burst waveforms according to the N inner trigger signals. In order to solve the technical problem that in the prior art, burst time intervals are fixed, the signal generator can meet the requirements of users for segmented burst, multiple burst time intervals can be set, and the burst waveforms are output in a segmented mode according to all the time intervals.

Chemical synthesis method of methyl 3-methyl-5-pyrazolylformate

The invention relates to a chemical synthesis method of methyl 3-methyl-5-pyrazolylformate.3-methylpyrazole used as the raw material is subjected to reactive hydrogen protection, carboxylation, esterification and deprotection to prepare the methyl 3-methyl-5-pyrazolylformate. The chemical synthesis method comprises the following steps: adding 3-methylpyrazole, p-methoxycyclite and sodium hydride into an N,N-dimethylformamide or dimethylsulfoxide organic solvent, and reacting to prepare 1-(4'-methoxybenzyl)-3-methylpyrazole; adding into a tetrahydrofuran organic solvent, reacting at certain temperature, and adding into dry ice after the reaction finishes to prepare 1-(4'-methoxybenzyl)-3-methyl-5-pyrazolylformic acid; adding thionyl chloride to react to obtain methyl 1-(4'-methoxybenzyl)-3-methyl-5-pyrazolylformate; and adding trifluoroacetic acid, and reacting at certain temperature to obtain the methyl 3-methyl-5-pyrazolylformate. The invention provides a high-efficiency synthesis method ...

Sweep signal generator capable of generating a plurality of frequency markers

The invention provides a sweep signal generator capable of generating a plurality of frequency markers. The sweep signal generator comprises a control unit, a sweep signal generating unit and a frequency marker generating unit. The sweep signal generating unit comprises a sweep state control unit, a sweep time accumulator and a sweep curve memory. The control unit is used for setting the sweep state and a sweep curve. The sweep state control unit generates a time control word according to the sweep state. The sweep time accumulator generates a read address according to the time control word. The sweep curve memory is used for generating a sweep point according to the sweep curve and the read address. The control unit is also used for reading frequency point enabling information. The frequency marker generating unit comprises a frequency point memory and a frequency marker shaping unit. The frequency point memory is used for generating a frequency point marker signal according to the frequency ...

Prediction method for residual stress of laser cladding deposited part

The invention belongs to the technical field of laser cladding, and particularly discloses a method for predicting residual stress of a laser cladding deposited part, which comprises the following steps of: 1, establishing a temperature field model, and inputting predicted material attributes and setting temperature boundary conditions in the temperature field model; 2, simulating a laser cladding deposition process by adopting a life-death unit technology, calculating a temperature field, and introducing the change of solid-liquid phase change latent heat in the calculation of the temperature field; 3, converting the temperature field model into a stress field model, and substituting the calculation result of the temperature field into the stress field model for phase calculation; and 4, calculating to obtain the mixed phase average linear expansion coefficient and the mixed phase average yield strength which influence the residual stress according to a phase calculation result, so as ...

Insulating particle of three-dimensional electrode reactor and application method thereof

The invention discloses an insulating particle of a three-dimensional electrode reactor and an application method of the insulating particle. The insulating particle is preparing by coating particle electrodes with the same material, shape and structure with polyimide. The application method includes the steps that insulating particles and the particle electrodes are evenly mixed according to a certain mass ratio or a certain volume ratio and then serve as bed layer filler of the three-dimensional electrode reactor to degrade organic pollutant in waste water. The insulating particles are resistant to acid, alkali and abrasion, good in insulating effect, long in service life, strong in adaptability and wide in application range, the problems of layering and insulation failure between the particle electrodes and materials such as quartz sand, glass beads and plastic are solved, the defects that cellulose acetate membranes are low in strength, not resistant to corrosion and abrasion and prone ...

Polyimide/ titanium dioxide hybrid fibers and preparation method thereof

The invention provides a polyimide/ titanium dioxide hybrid fiber. The hybrid fiber is characterized in that an organic phase of the material is polyimide, and an inorganic phase is TiO2 which accounts for 5 to 8% based on the mass fraction. The invention also provides a preparation method of the polyimide/ titanium dioxide hybrid fiber. According to the polyimide/ titanium dioxide hybrid fiber and the preparation method thereof, the method of hybridizing inorganic nanometer titania and polyimide, and the corresponding technical processes like spinning and wet drafting, stepped heating up and heat preserving type heat treating are adopted, and thus the mechanical performances, thermal stability and water resistance of polyimide fibers are obviously improved; in addition, the process is simple, various diamine and anhydride apply, the scope of supply of raw materials is wide, and the industrial production can be carried out easily.

Laser additive manufacturing zone control method based on model-free adaptive iterative learning

The invention belongs to the technical field of metal material additive manufacturing, and discloses a laser additive manufacturing partition control method based on model-free adaptive iterative learning, which comprises the following steps: layering a target to be printed along the height direction, and then dividing each layer into N sections of non-overlapping areas according to the scanning direction; and finally, process parameters of each area are controlled based on a model-free adaptive iterative learning control algorithm so as to realize layered and partitioned control of laser additive manufacturing. According to the method, each target layer to be printed is divided into a plurality of non-overlapped areas in the scanning direction, the process parameters of each area are adaptively controlled according to the historical information obtained from the previous layer in the process, and the potential instability of the deposition and scanning directions in the laser additive ...

Sodium polyoxyethylene fatty alcohol ether (9) octyl sulfosuccinate and its preparing process

Method for generating harmonic signal and harmonic signal generator

The invention relates to a harmonic signal generator. The harmonic signal generator generates a harmonic signal based on a DSP chip and an FPGA chip; the DSP chip is used for acquiring the amplitude coefficient, initial phase character and frequency control character of a fundamental wave, and the corresponding amplitude coefficient, initial phase character and frequency control character of each subharmonic wave and fundamental wave table data and transmitting to the FPGA chip; and the FPGA chip is used for generating the harmonic signal according information acquired by the DSP chip. The FPGA chip includes a harmonic signal component acquisition unit and a harmonic addition unit, wherein the harmonic signal component acquisition unit is used for generating components fi(kTs) of the harmonic signal according the information acquired by the DSP chip, and the harmonic addition unit is used for adding the components of the harmonic signal which are generated by the harmonic signal component ...

Device and method for improving pulse edge time resolution

The invention relates to a device and method for improving a pulse edge time resolution. The device comprises a pulse parameter processing unit used for processing and acquiring the frequency control character, time threshold value, ascent stage amplitude coefficient and decline stage amplitude coefficient and a pulse generation unit. The pulse generation unit includes a pulse period accumulation module used for generating a phase code; a comparison module used for comparing the phase code with the time threshold value to generate a pulse mark; a rising edge multiplication module used for multiplying the phase code by the ascent stage amplitude coefficient; a falling edge subtraction module used for subtracting the phase code from a decline stage time threshold value; a falling edge multiplication module used for multiplying a result output by the falling edge subtraction module by the decline stage amplitude coefficient; and a selection module used for judging a result generated by the ...

Modulator generating pi/4-DQPSK modulation signals, signal generator and method

The invention provides a modulator generating pi/4-DQPSK modulation signals, a signal generator and a method. After sending baseband signals to a modulation module by a controller, the modulation module generates directly deltaP, calculation is further carried out to obtain Pk, high three positions of the M-position carrier phase code are directly controller, digital pi/4-DQPSK modulation signals are directly generated by adopting the DDS technology, modulation signals of the final form are generated via digital to analog conversion, and a method of generating digital pi/4-DQPSK modulation signals is creatively invented. The method does not need to adopt a multiplier, and compared with the existing method of generating analog pi/4-DQPSK modulation signals, the structure is simple, the hardware resources are few, and system resources are saved.

Pigeon behavior monitoring device and method

The invention relates to the technical field of monitoring devices, in particular to a pigeon behavior monitoring device and method. Comprising a cage body, a monitoring assembly and a locking assembly, the monitoring assembly comprises a vertical guide rail, a moving support plate, an annular guide rail, a rotating block, a monitoring head, a moving component and a rotating component, the vertical guide rail is fixedly connected with the cage body, the moving support plate is slidably connected with the vertical guide rail through the moving component, and the annular guide rail is fixedly connected with the moving support plate; the rotating block is slidably connected with the annular guide rail, the monitoring head is fixedly connected with the rotating block, the moving component drives the moving supporting plate to move, the rotating component drives the rotating block to rotate, the moving component is started to enable the moving supporting plate to ascend and descend along the ...

Fishery germplasm resource block chain dual-storage method and system

The invention discloses a fishery germplasm resource block chain double-storage method, and the method comprises the following steps: S1, building a point-to-point permitted fishery germplasm resource block chain network model after a user completes the identity authentication through a supervision mechanism with fishery germplasm resource supervision responsibility; the invention also discloses a system of the fishery germplasm resource block chain double-storage method. The system comprises a client, an access server, a distributed verification server and a block chain system. According to the invention, the updated fishery germplasm resource transaction result corresponds to the updating pool, the repeated data of the updated fishery germplasm resource corresponds to the cache isolation pool, and the cache isolation pool stores and releases the repeated data of the updated fishery germplasm resource corresponding to the transaction result. Therefore, the fishery germplasm resource block ...

Preparation method of potassium-doped nano titanium dioxide photo-catalyst

The invention relates to a preparation method of a potassium-doped nano titanium dioxide photo-catalyst. According to the preparation method of the potassium-doped nano titanium dioxide photo-catalyst, potassium is taken as a doped element; potassium is doped into crystal lattices of TiO2, so that compounding of photoproduction electrons and cavities is stopped; a spectral response range is promoted to move to a visible region; and photo-catalytic activity of titanium dioxide is effectively improved. The potassium-doped nano titanium dioxide photo-catalyst prepared by the method is high in photo-catalytic activity and can process organic wastewater with good effect; the preparation method of the potassium-doped nano titanium dioxide photo-catalyst has the advantages that the process is simple, conditions are easily controlled, the production cost is low and the large-scale production is facilitated.

Method for preparing lithium chloride free from water

Method for improving strength, modulus, thermal stability and water resistance of polyimide fiber

The invention provides a method for improving the strength, modulus, thermal stability and water resistance of polyimide fiber. Surface modified nano silica is added to the polyimide fiber, and hybrid of silica with polyimide, spinning and wet drawing, thermal imidization and hot stretching treatment are conducted to effectively improve the strength, modulus, thermal stability and water resistance of polyimide fiber. The method of the invention has the advantages of simple operation, low cost and obvious effect, is applicable to polyimide fiber prepared from all kinds of diamine and dianhydride monomers, and overcomes the performance defects of single material fiber and conventional composite material fiber; and the prepared polyimide fiber has both the advantages of organic materials and inorganic materials, and can be widely used in the fields of aerospace, spaceflight, environment engineering, automobile industry, transportation and construction.

Sodium lauryl polyoxyethylene (7) octyl sulfosuccinate and its preparing process

Signal generator with burst synchronization function

The invention provides a signal generator with a burst synchronization function. The signal generator comprises a clock unit, a synchronization unit, a sampling unit and a waveform generating unit, wherein the clock unit is used for generating a first work clock and a second work clock; the synchronization unit is used for generating the delay clock of the first work clock according to the first work clock, the second work clock and an externally-input triggering pulse signal; the sampling unit is used for generating a triggering synchronization signal according to the delay clock and the triggering pulse signal; the waveform generating unit is used for generating waveforms according to the delay clock and the triggering pulse signal. The signal generator has the advantages that the problem that the burst output waveforms and the triggering pulse signal are non-synchronous is solved, and waveform jittering caused by the problem is eliminated.

Pseudo-random sequence generator based on FPGA (Field Programmable Gate Array) and generation method thereof

The embodiment of the invention discloses a pseudo-random sequence generator based on an FPGA and a generation method thereof, wherein the pseudo-random sequence generator comprises a control unit, a clock unit and an FPGA; the control unit is used for acquiring pseudo-random sequence parameters input by an user; user's commands are generated according to the pseudo-random sequence parameters and transmitted to the FPGA; the clock unit is used for providing clock pulses to the FPGA; the FPGA specifically includes a processor interface, a period accumulator, a pseudo-random sequence generation unit, an edge generation unit and a sequence formation unit. The pseudo-random sequence generator is characterized in that the FPGA is served as a main functional unit and few analog devices are supplemented, so that the pseudo-random sequence generator solves the technical problem that the code rate generated by the existing pseudo-random sequence generator has weak resolution ratio and precision.

Method and device for changing phase jump of phase shift keying (PSK)

The invention relates to the technical field of test and measurement, especially to a method and device for changing the phase jump of PSK. The device comprises a serial-to-parallel converter, a starting unit, a PSK word generation unit and a signal generator, wherein the serial-to-parallel converter is used for modulating a to-be-modulated baseband code element in a binary sequence and generating a modulation code element; the starting unit emits a phase jump signal when the modulation code element changes; the PSK word generation unit is used for generating PSK words in a transitional area within a period tau via a continuous function according to the phase jump signal; and the signal generator is used for generating a carrier wave whose phase continuously changes according to the PSK words. According to the method and device, the required phase shift is modulated, the transitional area ensures that the phase shift is continuous and smooth, thus, phase jump in the prior art is changed ...

Arbitrary waveform generator

The invention discloses an arbitrary waveform generator. A clock unit is used for generating a system clock. A dynamic random access memory (DRAM) is used for storing waveform data. A control unit is used for receiving a sampling rate. A waveform generation unit is used for generating a digital waveform according to the waveform data. A digital-analog conversion unit is used for converting the digital waveform into an analog waveform and then outputting the analog waveform. The waveform generation unit comprises a preread accumulator, a DRAM controller, a First In First Out (FIFO) memory and a phase accumulator. The preread accumulator is used for generating a preread accumulated value. The DRAM controller is used for getting waveform data out of the DRAM according to the preread accumulated value. The phase accumulator is used for generating an FIFO read enable signal according to the sampling rate. The FIFO memory is used for storing the waveform data and sending the waveform data to ...

Preparation method of p-chloropropiophenone

The invention discloses a preparation method of p-chloropropiophenone. Parafluorobenzoic acid and propionic acid serve as raw materials; in the presence of catalyst, the raw materials react to prepare the p-chloropropiophenone, and the catalyst is reduced iron powder. The invention adopts the novel catalyst to synthetize the p-chloropropiophenone, thereby simplifying the separation and purification processes. The invention has short reaction time and high product yield, the yield of the product can reach above 86%, and the invention has higher purity in the obtained product, low energy consumption, less environment pollution and low cost. The invention is a more ideal process for realizing industrialized production.

Signal generator with door control bursting function

The invention provides a signal generator with a door control bursting function. The signal generator comprises a waveform generating unit, a waveform output unit and a control unit, wherein the control unit is used for generating a trigger impulse signal and a trigger polar signal; the waveform generating unit is used for generating waveform signals; the waveform output unit is used for outputting a waveform signal; the signal generator further comprises a door control unit for generating a door control signal according to the trigger polar signal and the trigger impulse signal; the waveform generating unit generates the waveform signal according to the door control signal. The signal generator provided by the invention solves the problem in the prior art that the waveform phase generated due to the door control bursting function is discontinuous, avoids an overshoot phenomenon, improves transformation and communication error and reduces the damage on a tested instrument, and moreover, ...

Preparation method of p-fluorophenyl propyl ketone

The invention discloses a preparation method of p-fluorophenyl propyl ketone. Parafluorobenzoic acid and butyric acid are served as raw materials;and in the presence of a catalyst, the raw materials react to prepare the p-fluorophenyl propyl ketone. The catalyst is reduced iron powder. The invention adopts the parafluorobenzoic acid and the butyric acid as the raw materials to synthetize the p-fluorophenyl propyl ketone under the action of the catalyst, thereby simplifying the separation and purification processes. The invention has short reaction time and high product yield, the yield of the product can reach above 88%, and the invention has higher purity in the obtained product, low energy consumption, less environment pollution and low cost. The invention is a more ideal process for realizing industrialized production.

Powder raw material production difference removing device

The invention belongs to the technical field of powder raw material processing, and particularly relates to a powder raw material production foreign matter removing device which comprises a box body, supporting legs are assembled at the four corners of the lower side of the box body, a plurality of adsorption mechanisms distributed from top to bottom are assembled on the box body in a sliding mode, and each adsorption mechanism comprises a plurality of magnet rods distributed from left to right. The box body is provided with a plurality of sliding holes which are transversely distributed and matched with the magnet rods, the length of the magnet rods is two times that of the box body, a plurality of arc-shaped clamping pieces matched with the magnet rods are assembled on shells on the left side and the right side of the box body, and the ends, close to the centers of the magnet rods, of the arc-shaped clamping pieces deflect towards the side away from the box body. According to the invention ...

Biodegradable lumen closed clamp and manufacturing method thereof

The invention discloses a biodegradable lumen closed clamp and a manufacturing method thereof and belongs to the technical field of biological medicine, in particular to biodegradable medical disposable material for closing and cutting such lumen structures as blood vessels, cystic gall ducts and ureters in operation. The biodegradable lumen closed clamp body is flexible and strip-shaped and can be folded to close; the closed surface of the clamp body is provided with clamp teeth capable of being closed in a staggered mode, a cylinder-shaped slot is formed in the end, a clamp hammer which enters the cylinder-shaped slot is arranged at the other end, and all the parts make up the lumen closed clamp; the lumen closed clamp is manufactured through a free fused deposition modeling technology after mixing degradable material with hydroxyapatite according to a certain proportion. The biodegradable lumen closed clamp has good bio-compatibility and is capable of degrading in the body; the biodegradable ...